Other Name(s):

Brazilian Cocoa, Cacao Brésilien, Guarana Seed Extract, Guaranine, Paullinia cupana, Paullinia sorbilis, Zoom.


Guarana is a plant named for the Guarani tribe in the Amazon, who used the seeds to brew a drink. Today, guarana seeds are still used as medicine.

Guarana is used for weight loss, to enhance athletic performance, as a stimulant, and to reduce mental and physical fatigue. It is a frequent addition to energy and weight loss products.

Some people also use guarana to treat low blood pressure and chronic fatigue syndrome (CFS), and to prevent malaria and dysentery. It is also used to enhance sexual desire, to increase urine flow, and as an astringent.

Other uses include treatment of ongoing diarrhea, fever, heart problems, headache, joint pain, backache, and heat stress.

In food manufacturing, guarana has been used as a flavoring ingredient in beverages and candy.

How does it work?

Guarana contains caffeine. Caffeine works by stimulating the central nervous system (CNS), heart, and muscles. Guarana also contains theophylline and theobromine, which are chemicals similar to caffeine.

Uses & Effectiveness

Insufficient Evidence to Rate Effectiveness for...

  • Anxiety. Early research suggests that taking two tablets of a specific product (Euphytose) containing hawthorn, black horehound, passionflower, valerian, cola nut, and guarana three times daily for 28 days can reduce anxiety in some people. However, it is not clear if guarana alone is beneficial.
  • Mental performance. Early research in healthy people suggests that taking a single dose of guarana dry extract can improve thinking speed. However, other research suggests that taking guarana daily does not improve mental function in adults or older people.
  • Weight loss. Guarana might promote weight loss when used in combination with mate and damiana. There is also developing evidence that a specific combination product containing guarana, ephedra, and 17 other vitamins, minerals, and supplements (Metabolife-356) might help reduce weight by approximately 2.7 kg over eight weeks when used with a low-fat diet and exercise. However, more evidence is needed to rate guarana for this use.
  • Malaria.
  • Diarrhea.
  • Fever.
  • Headaches.
  • Heart problems.
  • Improvement of exercise endurance.
  • Improvement of short-term, high-intensity performance and power.
  • Increasing blood pressure in people who have low blood pressure.
  • Chronic fatigue syndrome (CFS).
  • Joint pain.
  • Fluid retention.
  • Other conditions.
More evidence is needed to rate guarana for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).


Vitamin D Deficiency: How Much Vitamin D Is Enough? See Slideshow

Side Effects

Guarana is LIKELY SAFE for most adults when consumed in amounts commonly found in foods.

Guarana is POSSIBLY SAFE when taken my mouth in medicinal amounts for a short time.

Guarana is POSSIBLY UNSAFE when taking by mouth in high doses for a long time. Doses greater than 250-300 mg daily have been linked to side effects. Side effects depend on the dose. At typical doses, the caffeine in guarana can cause insomnia, nervousness and restlessness, stomach irritation, nausea, vomiting, increased heart rate and blood pressure, rapid breathing, tremors, delirium, diuresis, and other side effects. Large guarana doses might cause headache, anxiety, agitation, ringing in the ears, pain when urinating, stomach cramps, and irregular heartbeats. People who take guarana regularly may experience caffeine withdrawal symptoms if they reduce their usual amount.

Guarana is LIKELY UNSAFE and even deadly, due to its caffeine content, when taken by mouth or injected in very high doses. The fatal dose of caffeine is estimated to be 10-14 grams (150-200 mg per kilogram; the “typical” man weighs about 70 kilograms, so a lethal dose of caffeine for this man would be 10,500-14,000 mg). This is quite a high dose. Consider that one cup of brewed coffee provides from 95-200 mg of caffeine. However, serious poisoning can occur at doses lower than 150-200 mg per kilogram depending on an individual's caffeine sensitivity or smoking behavior, age, and prior caffeine use.

Special Precautions & Warnings

Pregnancy and breast-feeding: Guarana is POSSIBLY SAFE for pregnant and breast feeding women when taken in amounts commonly found in foods. If you are pregnant or breast-feeding, guarana should be taken with caution due to the caffeine content. Small amounts are probably not harmful. However, taking guarana in high doses by mouth is POSSIBLY UNSAFE. Consuming more than 200 mg has been linked to an increased risk of miscarriage and other negative effects.

Anxiety: The caffeine in guarana might make feelings of anxiety worse.

Bleeding disorders: There is some evidence suggesting that the caffeine in guarana might make bleeding disorders worse, although this has not been reported in people. If you have a bleeding disorder, check with your healthcare provider before starting guarana.

Diabetes: Some research suggests that the caffeine in guarana may affect the way people with diabetes process sugar (glucose) and may complicate blood sugar control. There is also some interesting research that suggests caffeine may enhance the warning symptoms of low blood sugar in patients with type 1 diabetes. Some studies show that the symptoms of low blood sugar are more intense when they start in the absence of caffeine, but as low blood sugar continues, symptoms are greater with caffeine. This might increase the ability of diabetic patients to detect and treat low blood sugar. However, the downside is that caffeine might actually increase the number of low-sugar episodes. If you have diabetes, talk with your healthcare provider before starting guarana.

Diarrhea. Guarana contains caffeine. The caffeine in guarana, especially when taken in large amounts, can worsen diarrhea.

Irritable bowel syndrome (IBS): Guarana contains caffeine. The caffeine in guarana, especially when taken in large amounts, can worsen diarrhea and might worsen symptoms of IBS.

Heart disease: The caffeine in guarana might cause irregular heartbeat in certain people. Use with caution.

High blood pressure: Taking guarana might raise blood pressure in people with high blood pressure due to its caffeine content. However, this effect might be less in people who are regular coffee-drinkers or otherwise use caffeine on a regular basis.

Glaucoma: The caffeine in guarana increases the pressure inside the eye. The increase occurs within 30 minutes and lasts for at least 90 minutes after drinking caffeinated beverages.

Osteoporosis: The caffeine in guarana can flush calcium out of the body through the kidneys. This calcium loss might help to weaken bones. To minimize this problem, don't use more than 300 mg of caffeine per day. Taking calcium supplements may also help to offset these calcium losses. Postmenopausal women who have a genetic problem that affects how vitamin D is used by the body should use caffeine with caution.


AmphetaminesInteraction Rating: Major Do not take this combination.

Stimulant drugs such as amphetamines speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in guarana might also speed up the nervous system. Taking guarana along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

CocaineInteraction Rating: Major Do not take this combination.

Stimulant drugs such as cocaine speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in guarana might also speed up the nervous system. Taking guarana along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

EphedrineInteraction Rating: Major Do not take this combination.

Stimulant drugs speed up the nervous system. Caffeine (contained in guarana) and ephedrine are both stimulant drugs. Taking guarana along with ephedrine might cause too much stimulation and sometimes serious side effects and heart problems. Do not take caffeine-containing products and ephedrine at the same time.

Adenosine (Adenocard)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. The caffeine in guarana might block the affects of adenosine (Adenocard). Adenosine (Adenocard) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming guarana or other caffeine-containing products at least 24 hours before a cardiac stress test.

Antibiotics (Quinolone antibiotics)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Some antibiotics might decrease how quickly the body breaks down caffeine. Taking these antibiotics along with guarana can increase the risk of side effects including jitteriness, headache, increased heart rate, and other side effects.

Some antibiotics that decrease how quickly the body breaks down caffeine include ciprofloxacin (Cipro), enoxacin (Penetrex), norfloxacin (Chibroxin, Noroxin), sparfloxacin (Zagam), trovafloxacin (Trovan), and grepafloxacin (Raxar).

Cimetidine (Tagamet)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. The body breaks down caffeine to get rid of it. Cimetidine (Tagamet) can decrease how quickly your body breaks down caffeine. Taking cimetidine (Tagamet) along with guarana might increase the chance of caffeine side effects including jitteriness, headache, fast heartbeat, and others.

Clozapine (Clozaril)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down clozapine (Clozaril) to get rid of it. The caffeine in guarana seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking guarana along with clozapine (Clozaril) can increase the effects and side effects of clozapine (Clozaril).

Dipyridamole (Persantine)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. The caffeine in guarana might block the effects of dipyridamole (Persantine). Dipyridamole (Persantine) is often used by doctors to do a test on the heart. This test is called a cardiac stress test. Stop consuming guarana or other caffeine-containing products at least 24 hours before a cardiac stress test.

Disulfiram (Antabuse)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Disulfiram (Antabuse) can decrease how quickly the body gets rid of caffeine. Taking guarana (which contains caffeine) along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.

EstrogensInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down the caffeine in guarana to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking guarana along with estrogens can cause jitteriness, headache, fast heartbeat, and other side effects. If you take estrogens, limit your caffeine intake.

Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others.

Fluvoxamine (Luvox)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down the caffeine in guarana to get rid of it. Fluvoxamine (Luvox) can decrease how quickly the body breaks down caffeine. Taking guarana along with fluvoxamine (Luvox) might cause too much caffeine in the body, and increase the effects and side effects of caffeine.

LithiumInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

You body naturally gets rid of lithium. The caffeine in guarana can increase how quickly your body gets rid of lithium. If you take products that contain caffeine and you take lithium, stop taking caffeine products slowly. Stopping caffeine too quickly can increase the side effects of lithium.

Medications for asthma (Beta-adrenergic agonists)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. Caffeine can stimulate the heart. Some medications for asthma can also stimulate the heart. Taking caffeine with some medications for asthma might cause too much stimulation and cause heart problems.

Some medications for asthma include albuterol (Proventil, Ventolin, Volmax), metaproterenol (Alupent), terbutaline (Bricanyl, Brethine), and isoproterenol (Isuprel).

Medications for depression (MAOIs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. Taking guarana with these medications used for depression might cause serious side effects including fast heartbeat, high blood pressure, nervousness, and others.

Some of these medications used for depression include phenelzine (Nardil), tranylcypromine (Parnate), and others.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. Caffeine might slow blood clotting. Taking guarana along with medications that also slow clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), diclofenac (Voltaren, Cataflam, others), ibuprofen (Advil, Motrin, others), naproxen (Anaprox, Naprosyn, others), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, warfarin (Coumadin), and others.

NicotineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Stimulant drugs such as nicotine speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and increase your heart rate. The caffeine in guarana might also speed up the nervous system. Taking guarana along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

Pentobarbital (Nembutal)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The stimulant effects of the caffeine in guarana can block the sleep-producing effects of pentobarbital.

PhenylpropanolamineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The caffeine in guarana can stimulate the body. Phenylpropanolamine can also stimulate the body. Taking guarana along with phenylpropanolamine might cause too much stimulation and increase heartbeat, blood pressure and cause nervousness.

Riluzole (Rilutek)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down riluzole (Rilutek) to get rid of it. Taking guarana can decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole.

Stimulant drugsInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Stimulant drugs speed up the nervous system. By speeding up the nervous system, stimulant medications can make you feel jittery and speed up your heartbeat. Guarana contains caffeine, which can also speed up the nervous system. Taking guarana along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with guarana.

Some stimulant drugs include nicotine, cocaine, sympathomimetic amines, and amphetamines.

TheophyllineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. Caffeine works similarly to theophylline. Caffeine can also decrease how quickly the body gets rid of theophylline. Taking guarana along with theophylline might increase the effects and side effects of theophylline.

Verapamil (Calan, Covera, Isoptin, Verelan)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down the caffeine in guarana to get rid of it. Verapamil (Calan, Covera, Isoptin, Verelan) can decrease how quickly the body gets rid of caffeine. Taking guarana along with verapamil (Calan, Covera, Isoptin, Verelan) can increase the risk of caffeine side effects including jitteriness, headache, and an increased heartbeat.

AlcoholInteraction Rating: Minor Be cautious with this combination.Talk with your health provider.

The body breaks down the caffeine in guarana to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking guarana along with alcohol might cause too much caffeine in the bloodstream and caffeine side effects including jitteriness, headache, and fast heartbeat.

Birth control pills (Contraceptive drugs)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

The body breaks down the caffeine in guarana to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking guarana along with birth control pills can cause jitteriness, headache, fast heartbeat, and other side effects.

Some birth control pills include ethinyl estradiol and levonorgestrel (Triphasil), ethinyl estradiol and norethindrone (Ortho-Novum 1/35, Ortho-Novum 7/7/7), and others.

Fluconazole (Diflucan)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. The body breaks down caffeine to get rid of it. Fluconazole (Diflucan) might decrease how quickly the body gets rid of caffeine Taking guarana along with fluconazole (Diflucan) might increase the risk of caffeine side effects such as nervousness, anxiety, and insomnia.

Medications for diabetes (Antidiabetes drugs)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Guarana might increase blood sugar. Diabetes medications are used to lower blood sugar. By increasing blood sugar, guarana might decrease the effectiveness of diabetes medications. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

Mexiletine (Mexitil)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Guarana contains caffeine. The body breaks down caffeine to get rid of it. Mexiletine (Mexitil) can decrease how quickly the body breaks down caffeine. Taking mexiletine (Mexitil) along with guarana might increase the caffeine effects and side effects of guarana.

Terbinafine (Lamisil)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine (contained in guarana) to get rid of it. Terbinafine (Lamisil) can decrease how fast the body gets rid of caffeine and increase the risk of side effects including jitteriness, headache, increased heartbeat, and other effects.


The appropriate dose of guarana depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for guarana. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.


Akinyinka, O. O., Sowunmi, A., Honeywell, R., and Renwick, A. G. The effects of acute falciparum malaria on the disposition of caffeine and the comparison of saliva and plasma-derived pharmacokinetic parameters in adult Nigerians. Eur.J Clin Pharmacol 2000;56(2):159-165. View abstract.

Aldoori, W. H., Giovannucci, E. L., Stampfer, M. J., Rimm, E. B., Wing, A. L., and Willett, W. C. A prospective study of alcohol, smoking, caffeine, and the risk of duodenal ulcer in men. Epidemiology 1997;8(4):420-424. View abstract.

Aldridge, A., Aranda, J. V., and Neims, A. H. Caffeine metabolism in the newborn. Clin Pharmacol Ther 1979;25(4):447-453. View abstract.

Alstott, R. L., Miller, A. J., and Forney, R. B. Report of a human fatality due to caffeine. J.Forensic Sci. 1973;18(2):135-137. View abstract.

Antunes, E., Gordo, W. M., de Oliveira, J. F., Teixeira, C. E., Hyslop, S., and De, Nucci G. The relaxation of isolated rabbit corpus cavernosum by the herbal medicine Catuama and its constituents. Phytother.Res. 2001;15(5):416-421. View abstract.

Arditti, J., Bourdon, J. H., Spadari, M., de Haro, L., Richard, N., and Valli, M. [Ma Huang, from dietary supplement to abuse]. Acta Clin Belg.Suppl 2002;(1):34-36. View abstract.

Arnold, M. E., Petros, T. V., Beckwith, B. E., Coons, G., and Gorman, N. The effects of caffeine, impulsivity, and sex on memory for word lists. Physiol Behav. 1987;41(1):25-30. View abstract.

Arya, L. A., Myers, D. L., and Jackson, N. D. Dietary caffeine intake and the risk for detrusor instability: a case-control study. Obstet.Gynecol. 2000;96(1):85-89. View abstract.

Astrup, A., Toubro, S., Cannon, S., Hein, P., Breum, L., and Madsen, J. Caffeine: a double-blind, placebo-controlled study of its thermogenic, metabolic, and cardiovascular effects in healthy volunteers. Am.J.Clin.Nutr. 1990;51(5):759-767. View abstract.

Avato, P., Pesante, M. A., Fanizzi, F. P., and Santos, C. A. Seed oil composition of Paullinia cupana var. sorbilis (Mart.) Ducke. Lipids 2003;38(7):773-780. View abstract.

Baghkhani, L. and Jafari, M. Cardiovascular adverse reactions associated with Guarana: is there a causal effect? J.Herb.Pharmacother. 2002;2(1):57-61. View abstract.

Bak, A. A. and Grobbee, D. E. Caffeine, blood pressure, and serum lipids. Am.J.Clin Nutr. 1991;53(4):971-975. View abstract.

Bak, A. A. and Grobbee, D. E. Coffee, caffeine and hemostasis: a review. Neth.J.Med. 1990;37(5-6):242-246. View abstract.

Banner, W., Jr. and Czajka, P. A. Acute caffeine overdose in the neonate. Am.J Dis Child 1980;134(5):495-498. View abstract.

Barrett-Connor, E., Chang, J. C., and Edelstein, S. L. Coffee-associated osteoporosis offset by daily milk consumption. The Rancho Bernardo Study. JAMA 1-26-1994;271(4):280-283. View abstract.

Beach, C. A., Bianchine, J. R., and Gerber, N. The excretion of caffeine in the semen of men: pharmacokinetics and comparison of the concentrations in blood and semen. J Clin Pharmacol 1984;24(2-3):120-126. View abstract.

Belliardo, F., Martelli, A., and Valle, M. G. HPLC determination of caffeine and theophylline in Paullinia cupana Kunth (guarana) and Cola spp. samples. Z.Lebensm.Unters.Forsch. 1985;180(5):398-401. View abstract.

Bempong DK, Houghton PJ, and Steadman K. The xanthine content of guarana and its preparations. Int J Pharmacog 1993;31(3):175-181.

Bempong, D. K. and Houghton, P. J. Dissolution and absorption of caffeine from guarana. J.Pharm.Pharmacol. 1992;44(9):769-771. View abstract.

Benoni, H., Dallakian, P., and Taraz, K. Studies on the essential oil from guarana. Z.Lebensm.Unters.Forsch. 1996;203(1):95-98. View abstract.

Berube-Parent S, Pelletier C, Dore J, and Tremblay A. Effects of encapsulated green tea and Guarana extracts containing a mixture of epigallocatechin-3-gallate and caffeine on 24 h energy expenditure and fat oxidation in men. Br J Nutr 2005;94(3):432-436. View abstract.

Bikin D, Conrad KA, and Mayersohn M. Lack of influence of caffeine and aspirin on lithium elimination. Clin Res 1982;30(2):249A.

Blanchard, J. and Sawers, S. J. Comparative pharmacokinetics of caffeine in young and elderly men. J Pharmacokinet.Biopharm. 1983;11(2):109-126. View abstract.

Blanchard, J. and Sawers, S. J. The absolute bioavailability of caffeine in man. Eur.J.Clin.Pharmacol. 1983;24(1):93-98. View abstract.

Blanchard, J. Protein binding of caffeine in young and elderly males. J Pharm.Sci 1982;71(12):1415-1418. View abstract.

Boublik, J. H., Quinn, M. J., Clements, J. A., Herington, A. C., Wynne, K. N., and Funder, J. W. Coffee contains potent opiate receptor binding activity. Nature 1-20-1983;301(5897):246-248. View abstract.

Boutroy, M. J., Vert, P., Monin, P., Royer, R. J., and Royer-Morrot, M. J. Methylation of theophylline to caffeine in premature infants. Lancet 4-14-1979;1(8120):830. View abstract.

BOWDEN, K. Isolation from Paullinia pinnata Linn. of material with action on the frog isolated heart. Bri.Pharm.Chemother. 1962;18:173-174. View abstract.

Boyle, C. A., Berkowitz, G. S., LiVolsi, V. A., Ort, S., Merino, M. J., White, C., and Kelsey, J. L. Caffeine consumption and fibrocystic breast disease: a case-control epidemiologic study. J.Natl.Cancer Inst. 1984;72(5):1015-1019. View abstract.

Bracco, D., Ferrarra, J. M., Arnaud, M. J., Jequier, E., and Schutz, Y. Effects of caffeine on energy metabolism, heart rate, and methylxanthine metabolism in lean and obese women. Am J Physiol 1995;269(4 Pt 1):E671-E678. View abstract.

Brice C and Smith A. The effects of caffeine on simulated driving, subjective alertness and sustained attention. Hum Psychopharmacol Clin Exp 2001;16(7):523-531.

Brooks, P. G., Gart, S., Heldfond, A. J., Margolin, M. L., and Allen, A. S. Measuring the effect of caffeine restriction on fibrocystic breast disease: the role of graphic stress telethermometry as an objective monitor of disease. J Reprod Med 1981;26(6):279-282. View abstract.

Brown, C. A., Bolton-Smith, C., Woodward, M., and Tunstall-Pedoe, H. Coffee and tea consumption and the prevalence of coronary heart disease in men and women: results from the Scottish Heart Health Study. J.Epidemiol.Community Health 1993;47(3):171-175. View abstract.

Brown, S. L., Salive, M. E., Pahor, M., Foley, D. J., Corti, M. C., Langlois, J. A., Wallace, R. B., and Harris, T. B. Occult caffeine as a source of sleep problems in an older population. J.Am.Geriatr.Soc. 1995;43(8):860-864. View abstract.

Bruce, M. S. and Lader, M. Caffeine abstention in the management of anxiety disorders. Psychol.Med. 1989;19(1):211-214. View abstract.

Bryant CM, Dowell CJ, and Fairbrother G. A randomised trial of the effects of caffeine upon frequency, urgency and urge incontinence. Neurourology & Urodynamics 2000;19(4):501-502.

Bullough, B., Hindi-Alexander, M., and Fetouh, S. Methylxanthines and fibrocystic breast disease: a study of correlations. Nurse Pract. 1990;15(3):36-4. View abstract.

Bydlowski, S. P., D'Amico, E. A., and Chamone, D. A. An aqueous extract of guarana (Paullinia cupana) decreases platelet thromboxane synthesis. Braz.J.Med.Biol.Res. 1991;24(4):421-424. View abstract.

Bydlowski, S. P., Yunker, R. L., and Subbiah, M. T. A novel property of an aqueous guarana extract (Paullinia cupana): inhibition of platelet aggregation in vitro and in vivo. Braz.J.Med.Biol.Res. 1988;21(3):535-538. View abstract.

Caballero, T., Garcia-Ara, C., Pascual, C., Diaz-Pena, J. M., and Ojeda, A. Urticaria induced by caffeine. J.Investig.Allergol.Clin Immunol. 1993;3(3):160-162. View abstract.

Campos, A. R., Barros, A. I., Santos, F. A., and Rao, V. S. Guarana (Paullinia cupana Mart.) offers protection against gastric lesions induced by ethanol and indomethacin in rats. Phytother Res. 2003;17(10):1199-1202. View abstract.

Carlson, M. and Thompson, R. D. Liquid chromatographic determination of methylxanthines and catechins in herbal preparations containing guarana. J.AOAC Int. 1998;81(4):691-701. View abstract.

Chamone, D. A., Silva, M. I., Cassaro, C., Bellotti, G., Massumoto, C. M., and Fujimura, A. Y. Guaraná (Paullinia cupana) inhibits aggregation in whole blood. Thrombosis and Haemostasis 1987;58(1):474.

Chelsky, L. B., Cutler, J. E., Griffith, K., Kron, J., McClelland, J. H., and McAnulty, J. H. Caffeine and ventricular arrhythmias. An electrophysiological approach. JAMA 11-7-1990;264(17):2236-2240. View abstract.

Conlisk A and Galuska D. Is caffeine associated with bone mineral density in young adult women? JAMA 2001;285(6):713.

Curatolo, P. W. and Robertson, D. The health consequences of caffeine. Ann.Intern.Med. 1983;98(5 Pt 1):641-653. View abstract.

da Fonseca, C. A., Leal, J., Costa, S. S., and Leitao, A. C. Genotoxic and mutagenic effects of guarana (Paullinia cupana) in prokaryotic organisms. Mutat.Res. 1994;321(3):165-173. View abstract.

Dalvi, R. R. Acute and chronic toxicity of caffeine: a review. Vet Hum.Toxicol 1986;28(2):144-150. View abstract.

Daniels, J. W., Mole, P. A., Shaffrath, J. D., and Stebbins, C. L. Effects of caffeine on blood pressure, heart rate, and forearm blood flow during dynamic leg exercise. J.Appl.Physiol 1998;85(1):154-159. View abstract.

Davis, R. H. Does caffeine ingestion affect intraocular pressure?. Ophthalmology 1989;96(11):1680-1681. View abstract.

Dawber, T. R., Kannel, W. B., and Gordon, T. Coffee and cardiovascular disease. Observations from the Framingham study. N Engl J Med 10-24-1974;291(17):871-874. View abstract.

De Freitas, B. and Schwartz, G. Effects of caffeine in chronic psychiatric patients. Am.J.Psychiatry 1979;136(10):1337-1338. View abstract.

de Oliveira, J. F., Avila, A. S., Braga, A. C., de Oliveira, M. B., Boasquevisque, E. M., Jales, R. L., Cardoso, V. N., and Bernardo-Filho, M. Effect of extract of medicinal plants on the labeling of blood elements with Technetium-99m and on the morphology of red blood cells: I--a study with Paullinia cupana. Fitoterapia 2002;73(4):305-312. View abstract.

Debrah, K., Haigh, R., Sherwin, R., Murphy, J., and Kerr, D. Effect of acute and chronic caffeine use on the cerebrovascular, cardiovascular and hormonal responses to orthostasis in healthy volunteers. Clin Sci (Colch.) 1995;89(5):475-480. View abstract.

Dimaio, V. J. and Garriott, J. C. Lethal caffeine poisoning in a child. Forensic Sci. 1974;3(3):275-278. View abstract.

Dobmeyer, D. J., Stine, R. A., Leier, C. V., Greenberg, R., and Schaal, S. F. The arrhythmogenic effects of caffeine in human beings. N.Engl.J.Med. 4-7-1983;308(14):814-816. View abstract.

Drew AK and Dawson AH. Herbal xtreme: acute toxicity associated with intravenous guarana [abstract]. Journal of Toxicology - Clinical Toxicology 2000;38(2):235-236.

du, Boisgueheneuc F., Lannuzel, A., Caparros-Lefebvre, D., and De Broucker, T. [Cerebral infarction in a patient consuming MaHuang extract and guarana]. Presse Med 2-3-2001;30(4):166-167. View abstract.

Dulloo, A. G. and Miller, D. S. The thermogenic properties of ephedrine/methylxanthine mixtures: human studies. Int.J Obes. 1986;10(6):467-481. View abstract.

Dulloo, A. G., Geissler, C. A., Horton, T., Collins, A., and Miller, D. S. Normal caffeine consumption: influence on thermogenesis and daily energy expenditure in lean and postobese human volunteers. Am J Clin Nutr 1989;49(1):44-50. View abstract.

Edelstein, B. A., Keaton-Brasted, C., and Burg, M. M. Effects of caffeine withdrawal on nocturnal enuresis, insomnia, and behavior restraints. J.Consult Clin Psychol. 1984;52(5):857-862. View abstract.

Eggertsen, R., Andreasson, A., Hedner, T., Karlberg, B. E., and Hansson, L. Effect of coffee on ambulatory blood pressure in patients with treated hypertension. J.Intern.Med. 1993;233(4):351-355. View abstract.

Eisig, J. N., Zaterka, S., Massuda, H. K., and Bettarello, A. Coffee drinking in patients with duodenal ulcer and a control population. Scand J Gastroenterol. 1989;24(7):796-798. View abstract.

Elkins, R. N., Rapoport, J. L., Zahn, T. P., Buchsbaum, M. S., Weingartner, H., Kopin, I. J., Langer, D., and Johnson, C. Acute effects of caffeine in normal prepubertal boys. Am.J.Psychiatry 1981;138(2):178-183. View abstract.

Elta, G. H., Behler, E. M., and Colturi, T. J. Comparison of coffee intake and coffee-induced symptoms in patients with duodenal ulcer, nonulcer dyspepsia, and normal controls. Am J Gastroenterol. 1990;85(10):1339-1342. View abstract.

Ernster, V. L., Mason, L., Goodson, W. H., III, Sickles, E. A., Sacks, S. T., Selvin, S., Dupuy, M. E., Hawkinson, J., and Hunt, T. K. Effects of caffeine-free diet on benign breast disease: a randomized trial. Surgery 1982;91(3):263-267. View abstract.

Espinola, E. B., Dias, R. F., Mattei, R., and Carlini, E. A. Pharmacological activity of Guarana (Paullinia cupana Mart.) in laboratory animals. J.Ethnopharmacol. 1997;55(3):223-229. View abstract.

Fang, S., Sherwood, R. A., Gamsu, H. R., Marsden, J. T., Peters, T. J., and Greenough, A. Comparison of the effects of theophylline and caffeine on serum erythropoietin concentration in premature infants. Eur.J Pediatr. 1998;157(5):406-409. View abstract.

Freestone, S. and Ramsay, L. E. Effect of coffee and cigarette smoking on the blood pressure of untreated and diuretic-treated hypertensive patients. Am.J.Med. 1982;73(3):348-353. View abstract.

Freestone, S., Yeo, W. W., and Ramsay, L. E. Effect of coffee and cigarette smoking on the blood pressure of patients with accelerated (malignant) hypertension. J.Hum.Hypertens. 1995;9(2):89-91. View abstract.

Fukumasu, H., Silva, T. C., Avanzo, J. L., Lima, C. E., Mackowiak, I. I., Atroch, A., Spinosa, H. D., Moreno, F. S., and Dagli, M. L. Chemopreventive effects of Paullinia cupana Mart var. sorbilis, the guarana, on mouse hepatocarcinogenesis. Cancer Lett. 5-7-2005; View abstract.

Galduroz, J. C. and Carlini, E. A. The effects of long-term administration of guarana on the cognition of normal, elderly volunteers. Sao Paulo Med.J. 1996;114(1):1073-1078. View abstract.

Galduroz, J. C. and Carlini, Ede A. Acute effects of the Paulinia cupana, "Guarana" on the cognition of normal volunteers. Sao Paulo Med.J. 1994;112(3):607-611. View abstract.

Gallerani, M., Zanotti, C., Menozzi, L., Montezemolo, A., Monetti, V. C., and Tola, M. R. Barbiturate, analgesic, and caffeine withdrawal. Am.J.Emerg.Med. 1994;12(5):603-605. View abstract.

Gancedo SQ, Freire P, Fernandez Rivas M, and et al. Urticaria from caffeine. J Allerg Clin Immunol 1991;88:680-681.

Garrett, B. E. and Griffiths, R. R. Physical dependence increases the relative reinforcing effects of caffeine versus placebo. Psychopharmacology (Berl) 1998;139(3):195-202. View abstract.

Gilliland K and Bullock W. Caffeine: A potential drug of abuse. Adv Alcohol Subst Abuse 1984;3(1-2):53-73.

Glore, S. and Ricker, A. Trigeminal neuralgia: case study of pain cessation with a low-caffeine diet. J.Am.Diet.Assoc. 1991;91(9):1120-1121. View abstract.

Grant, D. M., Tang, B. K., and Kalow, W. Variability in caffeine metabolism. Clin Pharmacol Ther 1983;33(5):591-602. View abstract.

Greden, J. F., Victor, B. S., Fontaine, P., and Lubetsky, M. Caffeine-withdrawal headache: a clinical profile. Psychosomatics 1980;21(5):411-418. View abstract.

Greenstadt, L., Yang, L., and Shapiro, D. Caffeine, mental stress, and risk for hypertension: a cross-cultural replication. Psychosom.Med 1988;50(1):15-22. View abstract.

Griffiths, R. R. and Chausmer, A. L. Caffeine as a model drug of dependence: recent developments in understanding caffeine withdrawal, the caffeine dependence syndrome, and caffeine negative reinforcement. Nihon Shinkei Seishin Yakurigaku Zasshi 2000;20(5):223-231. View abstract.

Griffiths, R. R., Evans, S. M., Heishman, S. J., Preston, K. L., Sannerud, C. A., Wolf, B., and Woodson, P. P. Low-dose caffeine physical dependence in humans. J Pharmacol Exp Ther 1990;255(3):1123-1132. View abstract.

Haller, C. A., Jacob, P., and Benowitz, N. L. Short-term metabolic and hemodynamic effects of ephedra and guarana combinations. Clin.Pharmacol.Ther. 2005;77(6):560-571. View abstract.

Harris, S. S. and Dawson-Hughes, B. Caffeine and bone loss in healthy postmenopausal women. Am J Clin Nutr 1994;60(4):573-578. View abstract.

Henman, A. R. Guarana (Paullinia cupana var. sorbilis): ecological and social perspectives on an economic plant of the central Amazon basin. J.Ethnopharmacol. 1982;6(3):311-338. View abstract.

Heyden, S. and Muhlbaier, L. H. Prospective study of "fibrocystic breast disease" and caffeine consumption. Surgery 1984;96(3):479-484. View abstract.

Hinkle, P. E., Coffey, C. E., Weiner, R. D., Cress, M., and Christison, C. Use of caffeine to lengthen seizures in ECT. Am.J.Psychiatry 1987;144(9):1143-1148. View abstract.

Hoffmann, F. L., Garcia-Cruz, C. H., Vinturim, T. M., and Pagnocca, F. C. Survey of the microbiological quality of nonalcoholic carbonated beverages. Folia Microbiol.(Praha) 1997;42(3):199-202. View abstract.

Horst K, Buxton RE, and Robinson WD. The effect of the habitual use of coffee of decaffeinated coffee upon blood pressure and certain motor reactions of normal young men. J Pharmacol Exp Ther 1934;52:322-337.

Hughes, J. R., Higgins, S. T., Bickel, W. K., Hunt, W. K., Fenwick, J. W., Gulliver, S. B., and Mireault, G. C. Caffeine self-administration, withdrawal, and adverse effects among coffee drinkers. Arch.Gen.Psychiatry 1991;48(7):611-617. View abstract.

James, J. E. Chronic effects of habitual caffeine consumption on laboratory and ambulatory blood pressure levels. J.Cardiovasc.Risk 1994;1(2):159-164. View abstract.

James, J. E. Is habitual caffeine use a preventable cardiovascular risk factor? Lancet 1-25-1997;349(9047):279-281. View abstract.

Jee, S. H., He, J., Whelton, P. K., Suh, I., and Klag, M. J. The effect of chronic coffee drinking on blood pressure: a meta-analysis of controlled clinical trials. Hypertension 1999;33(2):647-652. View abstract.

Johnsen O, Eliasson R, and Abdel-Kadar MM. Effects of caffeine on the motility and metabolism of human spermatozoa. Andrologia 1974;6(1):53-58.

Kamimori, G. H., Somani, S. M., Knowlton, R. G., and Perkins, R. M. The effects of obesity and exercise on the pharmacokinetics of caffeine in lean and obese volunteers. Eur J Clin Pharmacol 1987;31(5):595-600. View abstract.

Karacan, I., Thornby, J. I., Anch, M., Booth, G. H., Williams, R. L., and Salis, P. J. Dose-related sleep disturbances induced by coffee and caffeine. Clin Pharmacol Ther 1976;20(6):682-689. View abstract.

Kawachi, I., Colditz, G. A., and Stone, C. B. Does coffee drinking increase the risk of coronary heart disease? Results from a meta-analysis. Br Heart J 1994;72(3):269-275. View abstract.

Kendler, K. S. and Prescott, C. A. Caffeine intake, tolerance, and withdrawal in women: a population-based twin study. Am.J.Psychiatry 1999;156(2):223-228. View abstract.

Kennedy, D. O., Haskell, C. F., Wesnes, K. A., and Scholey, A. B. Improved cognitive performance in human volunteers following administration of guarana (Paullinia cupana) extract: comparison and interaction with Panax ginseng. Pharmacol Biochem Behav 2004;79(3):401-411. View abstract.

Keuchel, I., Kohnen, R., and Lienert, G. A. The effects of alcohol and caffeine on concentration test performance. Arzneimittelforschung. 1979;29(6):973-975. View abstract.

Khodesevick AP. Fatal caffeine poisoning (case from practice). Farmakol Toksikol 1956;19(suppl):62.

Koczapski, A., Paredes, J., Kogan, C., Ledwidge, B., and Higenbottam, J. Effects of caffeine on behavior of schizophrenic inpatients. Schizophr.Bull. 1989;15(2):339-344. View abstract.

Kulkarni, P. B. and Dorand, R. D. Caffeine toxicity in a neonate. Pediatrics 1979;64(2):254-255. View abstract.

Lane, J. D. and Phillips-Bute, B. G. Caffeine deprivation affects vigilance performance and mood. Physiol Behav. 1998;65(1):171-175. View abstract.

Lane, J. D. and Williams, R. B., Jr. Cardiovascular effects of caffeine and stress in regular coffee drinkers. Psychophysiology 1987;24(2):157-164. View abstract.

Lane, J. D. Effects of brief caffeinated-beverage deprivation on mood, symptoms, and psychomotor performance. Pharmacol Biochem.Behav 1997;58(1):203-208. View abstract.

Lang, T., Degoulet, P., Aime, F., Fouriaud, C., Jacquinet-Salord, M. C., Laprugne, J., Main, J., Oeconomos, J., Phalente, J., and Prades, A. Relation between coffee drinking and blood pressure: analysis of 6,321 subjects in the Paris region. Am.J Cardiol. 12-1-1983;52(10):1238-1242. View abstract.

Lawson, D. H., Jick, H., and Rothman, K. J. Coffee and tea consumption and breast disease. Surgery 1981;90(5):801-803. View abstract.

Levinson, W. and Dunn, P. M. Nonassociation of caffeine and fibrocystic breast disease. Arch.Intern.Med. 1986;146(9):1773-1775. View abstract.

Levy, M. and Zylber-Katz, E. Caffeine metabolism and coffee-attributed sleep disturbances. Clin Pharmacol Ther 1983;33(6):770-775. View abstract.

Li-Neng Y, Greenstadt L, and Shapiro D. Effects of caffeine on blood pressure: A cross-cultural comparison. Psychophysiology 1983;20:457.

Lieberman, H. R. The effects of ginseng, ephedrine, and caffeine on cognitive performance, mood and energy. Nutr Rev 2001;59(4):91-102. View abstract.

Lubin, F., Ron, E., Wax, Y., Black, M., Funaro, M., and Shitrit, A. A case-control study of caffeine and methylxanthines in benign breast disease. JAMA 4-26-1985;253(16):2388-2392. View abstract.

Lucas, P. B., Pickar, D., Kelsoe, J., Rapaport, M., Pato, C., and Hommer, D. Effects of the acute administration of caffeine in patients with schizophrenia. Biol.Psychiatry 7-1-1990;28(1):35-40. View abstract.

Mace, J. Toxicity of caffeine. J Pediatr 1978;92(2):345-346. View abstract.

Marshall, J., Graham, S., and Swanson, M. Caffeine consumption and benign breast disease: a case-control comparison. Am.J.Public Health 1982;72(6):610-612. View abstract.

Marx, F. Analysis of guarana seeds: II. Studies on the composition of the tannin fraction. Zeitschrift Fuer Lebensmittel Untersuchung Und Forschung 1990;190(5):429-431.

Marx, F. and et al. Analysis of guaraná (

Mattei, R., Dias, R. F., Espinola, E. B., Carlini, E. A., and Barros, S. B. Guarana (Paullinia cupana): toxic behavioral effects in laboratory animals and antioxidants activity in vitro. J.Ethnopharmacol. 1998;60(2):111-116. View abstract.

Mayo, K. M., Falkowski, W., and Jones, C. A. Caffeine: use and effects in long-stay psychiatric patients. Br.J.Psychiatry 1993;162:543-545. View abstract.

McManamy MC and Schube PG. Caffeine intoxication: report of a case the symptoms of which amounted to a psychosis. New England Journal of Medicine 1936;215:616-620.

Miura, T., Tatara, M., Nakamura, K., and Suzuki, I. Effect of guarana on exercise in normal and epinephrine-induced glycogenolytic mice. Biol.Pharm.Bull. 1998;21(6):646-648. View abstract.

Moraes VLG, Santos LFM, Castro SB, Loureiro LH, Lima OA, Souza MLM, Yien LMK, Rossi-Bergmann B, and Costa SS. Inhibition of lymphocyte activation by extracts and fractions of Kalanchoe, Alternanthera, Paullinia and Mikania species. Phytomedicine 1994;1:199-204.

Morano, A., Jimenez-Jimenez, F. J., Molina, J. A., and Antolin, M. A. Risk-factors for Parkinson's disease: case-control study in the province of Caceres, Spain. Acta Neurol.Scand 1994;89(3):164-170. View abstract.

Morton, J. F. Widespread tannin intake via stimulants and masticatories, especially guarana, kola nut, betel vine, and accessories. Basic Life Sci 1992;59:739-765. View abstract.

Myers, M. G. and Harris, L. High dose caffeine and ventricular arrhythmias. Can.J Cardiol. 1990;6(3):95-98. View abstract.

Myers, M. G., Harris, L., Leenen, F. H., and Grant, D. M. Caffeine as a possible cause of ventricular arrhythmias during the healing phase of acute myocardial infarction. Am.J Cardiol. 5-1-1987;59(12):1024-1028. View abstract.

Nagesh, R. V. and Murphy, K. A., Jr. Caffeine poisoning treated by hemoperfusion. Am.J.Kidney Dis. 1988;12(4):316-318. View abstract.

Neims AH, Bailey J, and Aldridge A. Disposition of caffeine during and after pregnancy. Clin Res 1979;27:236A.

Nussberger, J., Mooser, V., Maridor, G., Juillerat, L., Waeber, B., and Brunner, H. R. Caffeine-induced diuresis and atrial natriuretic peptides. J Cardiovasc.Pharmacol 1990;15(5):685-691. View abstract.

Nyska, A., Murphy, E., Foley, J. F., Collins, B. J., Petranka, J., Howden, R., Hanlon, P., and Dunnick, J. K. Acute hemorrhagic myocardial necrosis and sudden death of rats exposed to a combination of ephedrine and caffeine. Toxicol.Sci. 2005;83(2):388-396. View abstract.

O'Dea, J. A. Consumption of nutritional supplements among adolescents: usage and perceived benefits. Health Educ.Res. 2003;18(1):98-107. View abstract.

Ooms, T. G., Khan, S. A., and Means, C. Suspected caffeine and ephedrine toxicosis resulting from ingestion of an herbal supplement containing guarana and ma huang in dogs: 47 cases (1997-1999). J Am Vet Med Assoc 1-15-2001;218(2):225-229. View abstract.

Parsons, W. D. and Neims, A. H. Effect of smoking on caffeine clearance. Clin Pharmacol Ther 1978;24(1):40-45. View abstract.

Parsons, W. D. and Neims, A. H. Prolonged half-life of caffeine in healthy tem newborn infants. J Pediatr. 1981;98(4):640-641. View abstract.

Parsons, W. D. and Pelletier, J. G. Delayed elimination of caffeine by women in the last 2 weeks of pregnancy. Can.Med.Assoc.J 9-1-1982;127(5):377-380. View abstract.

Phillips-Bute, B. G. and Lane, J. D. Caffeine withdrawal symptoms following brief caffeine deprivation. Physiol Behav. 12-31-1997;63(1):35-39. View abstract.

Pincomb, G. A., Lovallo, W. R., McKey, B. S., Sung, B. H., Passey, R. B., Everson, S. A., and Wilson, M. F. Acute blood pressure elevations with caffeine in men with borderline systemic hypertension. Am.J Cardiol. 2-1-1996;77(4):270-274. View abstract.

Pincomb, G. A., Lovallo, W. R., Passey, R. B., Whitsett, T. L., Silverstein, S. M., and Wilson, M. F. Effects of caffeine on vascular resistance, cardiac output and myocardial contractility in young men. Am.J Cardiol. 7-1-1985;56(1):119-122. View abstract.

Pizziol, A., Tikhonoff, V., Paleari, C. D., Russo, E., Mazza, A., Ginocchio, G., Onesto, C., Pavan, L., Casiglia, E., and Pessina, A. C. Effects of caffeine on glucose tolerance: a placebo-controlled study. Eur.J Clin Nutr. 1998;52(11):846-849. View abstract.

Pola, J., Subiza, J., Armentia, A., Zapata, C., Hinojosa, M., Losada, E., and Valdivieso, R. Urticaria caused by caffeine. Ann.Allergy 1988;60(3):207-208. View abstract.

Prineas, R. J., Jacobs, D. R., Jr., Crow, R. S., and Blackburn, H. Coffee, tea and VPB. J Chronic.Dis 1980;33(2):67-72. View abstract.

Reeves, R. R., Struve, F. A., and Patrick, G. Somatic dysfunction increase during caffeine withdrawal. J.Am.Osteopath.Assoc. 1997;97(8):454-456. View abstract.

Rejent T, Michalek R, and Krajewski M. Caffeine fatality with coincident ephedrine. Bull Int Assoc Forensic Toxicol 1981;16:18-19.

Robelin, M. and Rogers, P. J. Mood and psychomotor performance effects of the first, but not of subsequent, cup-of-coffee equivalent doses of caffeine consumed after overnight caffeine abstinence. Behav.Pharmacol 1998;9(7):611-618. View abstract.

Roberts, A. T., Jonge-Levitan, L., Parker, C. C., and Greenway, F. The effect of an herbal supplement containing black tea and caffeine on metabolic parameters in humans. Altern Med Rev 2005;10(4):321-325. View abstract.

Robertson, D., Frolich, J. C., Carr, R. K., Watson, J. T., Hollifield, J. W., Shand, D. G., and Oates, J. A. Effects of caffeine on plasma renin activity, catecholamines and blood pressure. N.Engl.J Med. 1-26-1978;298(4):181-186. View abstract.

Rogers, P. J. and Dernoncourt, C. Regular caffeine consumption: a balance of adverse and beneficial effects for mood and psychomotor performance. Pharmacol Biochem.Behav. 1998;59(4):1039-1045. View abstract.

Rommelspacher, H. [Guarana]. Dtsch.Med.Wochenschr. 3-17-1995;120(11):384. View abstract.

Rosenberg, L., Miller, D. R., Helmrich, S. P., Kaufman, D. W., Schottenfeld, D., Stolley, P. D., and Shapiro, S. Breast cancer and the consumption of coffee. Am.J.Epidemiol. 1985;122(3):391-399. View abstract.

Rosengren, A. and Wilhelmsen, L. Coffee, coronary heart disease and mortality in middle-aged Swedish men: findings from the Primary Prevention Study. J Intern Med 1991;230(1):67-71. View abstract.

Rosmarin, P. C., Applegate, W. B., and Somes, G. W. Coffee consumption and blood pressure: a randomized, crossover clinical trial. J.Gen.Intern.Med. 1990;5(3):211-213. View abstract.

Roth JA, Ivy AC, and Atkinson AJ. Caffeine and "peptic" ulcer: relation of caffeine and caffeine-containing beverages to the pathogenesis, diagnosis and management of peptic ulcer. JAMA 1944;126:814-820.

Rowland D and Mace J. Caffeine (no-doz) poisoning in childhood. West J Med 1976;124:52-53.

Ryall JE. Caffeine and ephedrine fatality. Bull Int Assoc Forensic Toxicol 1984;17:13.

Salvadori, M. C., Rieser, E. M., Ribeiro Neto, L. M., and Nascimento, E. S. Determination of xanthines by high-performance liquid chromatography and thin-layer chromatography in horse urine after ingestion of Guarana powder. Analyst 1994;119(12):2701-2703. View abstract.

Santa, Maria A., Lopez, A., Diaz, M. M., Munoz-Mingarro, D., and Pozuelo, J. M. Evaluation of the toxicity of guarana with in vitro bioassays. Ecotoxicol.Environ.Saf 1998;39(3):164-167. View abstract.

Schlemmer RF, Heinze WJ, Asta CL, and et al. Caffeine potentiates phenylpropanolamine lethality but not motor behavior. Fed Proc 1984;43:572.

Schoenfeld, C., Amelar, R. D., and Dubin, L. Stimulation of ejaculated human spermatozoa by caffeine. A preliminary report. Fertil.Steril. 1973;24(10):772-775. View abstract.

Shirlow, M. J. and Mathers, C. D. A study of caffeine consumption and symptoms; indigestion, palpitations, tremor, headache and insomnia. Int.J.Epidemiol. 1985;14(2):239-248. View abstract.

Shorofsky, M. A. and Lamm, R. N. Caffeine-withdrawal headache and fasting. N.Y.State J.Med. 1977;77(2):217-218. View abstract.

Shum, S., Seale, C., Hathaway, D., Chucovich, V., and Beard, D. Acute caffeine ingestion fatalities: management issues. Vet.Hum.Toxicol. 1997;39(4):228-230. View abstract.

Sicard, B. A., Perault, M. C., Enslen, M., Chauffard, F., Vandel, B., and Tachon, P. The effects of 600 mg of slow release caffeine on mood and alertness. Aviat.Space Environ.Med. 1996;67(9):859-862. View abstract.

Silverman, K., Evans, S. M., Strain, E. C., and Griffiths, R. R. Withdrawal syndrome after the double-blind cessation of caffeine consumption. N.Engl.J.Med. 10-15-1992;327(16):1109-1114. View abstract.

Smith, A. P., Kendrick, A. M., and Maben, A. L. Effects of breakfast and caffeine on performance and mood in the late morning and after lunch. Neuropsychobiology 1992;26(4):198-204. View abstract.

Smits, P., Corstens, F. H., Aengevaeren, W. R., Wackers, F. J., and Thien, T. False-negative dipyridamole-thallium-201 myocardial imaging after caffeine infusion. J Nucl.Med. 1991;32(8):1538-1541. View abstract.

Smits, P., Temme, L., and Thien, T. The cardiovascular interaction between caffeine and nicotine in humans. Clin Pharmacol Ther 1993;54(2):194-204. View abstract.

Stein, M. A., Krasowski, M., Leventhal, B. L., Phillips, W., and Bender, B. G. Behavioral and cognitive effects of methylxanthines. A meta-analysis of theophylline and caffeine. Arch.Pediatr.Adolesc.Med. 1996;150(3):284-288. View abstract.

Stensvold, I. and Tverdal, A. The relationship of coffee consumption to various self-reported cardiovascular events in middle-aged Norwegian men and women. Scand J Soc Med 1995;23(2):103-109. View abstract.

Stensvold, I., Tverdal, A., and Foss, O. P. The effect of coffee on blood lipids and blood pressure. Results from a Norwegian cross-sectional study, men and women, 40-42 years. J Clin Epidemiol. 1989;42(9):877-884. View abstract.

Stillner, V., Popkin, M. K., and Pierce, C. M. Caffeine-induced delirium during prolonged competitive stress. Am.J.Psychiatry 1978;135(7):855-856. View abstract.

Sumbaev, V. V. and Rozanov, A. I. [Effect of caffeine on xanthine oxidase activity]. Ukr.Biokhim.Zh. 1997;69(5-6):196-200. View abstract.

Sung, B. H., Lovallo, W. R., Whitsett, T., and Wilson, M. F. Caffeine elevates blood pressure response to exercise in mild hypertensive men. Am.J.Hypertens. 1995;8(12 Pt 1):1184-1188. View abstract.

Sung, B. H., Whitsett, T. L., Lovallo, W. R., al'Absi, M., Pincomb, G. A., and Wilson, M. F. Prolonged increase in blood pressure by a single oral dose of caffeine in mildly hypertensive men. Am.J Hypertens. 1994;7(8):755-758. View abstract.

Superko, H. R., Myll, J., DiRicco, C., Williams, P. T., Bortz, W. M., and Wood, P. D. Effects of cessation of caffeinated-coffee consumption on ambulatory and resting blood pressure in men. Am J Cardiol 4-15-1994;73(11):780-784. View abstract.

Sutherland, D. J., McPherson, D. D., Renton, K. W., Spencer, C. A., and Montague, T. J. The effect of caffeine on cardiac rate, rhythm, and ventricular repolarization. Analysis of 18 normal subjects and 18 patients with primary ventricular dysrhythmia. Chest 1985;87(3):319-324. View abstract.

Tassaneeyakul, W., Birkett, D. J., McManus, M. E., Tassaneeyakul, W., Veronese, M. E., Andersson, T., Tukey, R. H., and Miners, J. O. Caffeine metabolism by human hepatic cytochromes P450: contributions of 1A2, 2E1 and 3A isoforms. Biochem.Pharmacol 5-18-1994;47(10):1767-1776. View abstract.

Tisdell R, Iacobucci M, and Snodgrass W. Caffeine poisoning in an adult: survival with a serum concentration of 400 mg/L and need for adenosine agonist antidotes. Vet Hum Toxicol 1986;28(5):492.

Tondo, L. and Rudas, N. The course of a seasonal bipolar disorder influenced by caffeine. J.Affect.Disord. 1991;22(4):249-251. View abstract.

Tuomilehto, J., Tuomilehto-Wolf, E., Virtala, E., and LaPorte, R. Coffee consumption as trigger for insulin dependent diabetes mellitus in childhood. BMJ 3-10-1990;300(6725):642-643. View abstract.

Van Dusseldorp, M., Smits, P., Lenders, J. W., Temme, L., Thien, T., and Katan, M. B. Effects of coffee on cardiovascular responses to stress: a 14-week controlled trial. Psychosom.Med. 1992;54(3):344-353. View abstract.

Van Dusseldorp, M., Smits, P., Thien, T., and Katan, M. B. Effect of decaffeinated versus regular coffee on blood pressure. A 12-week, double-blind trial. Hypertension 1989;14(5):563-569. View abstract.

Wald, A., Back, C., and Bayless, T. M. Effect of caffeine on the human small intestine. Gastroenterology 1976;71(5):738-742. View abstract.

Walsh, I., Wasserman, G. S., Mestad, P., and Lanman, R. C. Near-fatal caffeine intoxication treated with peritoneal dialysis. Pediatr.Emerg.Care 1987;3(4):244-249. View abstract.

Weckerle, C. S., Stutz, M. A., and Baumann, T. W. Purine alkaloids in Paullinia. Phytochemistry 2003;64(3):735-742. View abstract.

White, B. C., Lincoln, C. A., Pearce, N. W., Reeb, R., and Vaida, C. Anxiety and muscle tension as consequences of caffeine withdrawal. Science 9-26-1980;209(4464):1547-1548. View abstract.

Wrenn, K. D. and Oschner, I. Rhabdomyolysis induced by a caffeine overdose. Ann.Emerg.Med. 1989;18(1):94-97. View abstract.

Yu, G., Maskray, V., Jackson, S. H., Swift, C. G., and Tiplady, B. A comparison of the central nervous system effects of caffeine and theophylline in elderly subjects. Br.J Clin Pharmacol 1991;32(3):341-345. View abstract.

Abernethy DR, Todd EL. Impairment of caffeine clearance by chronic use of low-dose oestrogen-containing oral contraceptives. Eur J Clin Pharmacol 1985;28:425-8. View abstract.

Acheson KJ, Gremaud G, Meirim I, et al. Metabolic effects of caffeine in humans: lipid oxidation or futile cycling? Am J Clin Nutr 2004;79:40-6. View abstract.

Akhtar S, Wood G, Rubin JS, et al. Effect of caffeine on the vocal folds: a pilot study. J Laryngol Otol 1999;113:341-5. View abstract.

Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13. View abstract.

American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk. Pediatrics 2001;108:776-89. View abstract.

Andersen T, Fogh J. Weight loss and delayed gastric emptying following a South American herbal preparation in overweight patients. J Hum Nutr Diet 2001;14:243-50. View abstract.

Anderson BJ, Gunn TR, Holford NH, Johnson R. Caffeine overdose in a premature infant: clinical course and pharmacokinetics. Anaesth Intensive Care 1999;27:307-11. View abstract.

Aqel RA, Zoghbi GJ, Trimm JR, et al. Effect of caffeine administered intravenously on intracoronary-administered adenosine-induced coronary hemodynamics in patients with coronary artery disease. Am J Cardiol 2004;93:343-6. View abstract.

Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3. View abstract.

Avisar R, Avisar E, Weinberger D. Effect of coffee consumption on intraocular pressure. Ann Pharmacother 2002;36:992-5.. View abstract.

Bara AI, Barley EA. Caffeine for asthma. Cochrane Database Syst Rev 2001;4:CD001112.. View abstract.

Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403. View abstract.

Benowitz NL, Osterloh J, Goldschlager N, et al. Massive catecholamine release from caffeine poisoning. JAMA 1982;248:1097-8. View abstract.

Boozer CN, Nasser JA, Heymsfield SB, et al. An herbal supplement containing Ma Huang-Guarana for weight loss: a randomized, double-blind trial. Int J Obes Relat Metab Disord 2001;25:316-24. View abstract.

Bourin M, Bougerol T, Guitton B, Broutin E. A combination of plant extracts in the treatment of outpatients with adjustment disorder with anxious mood: controlled study vs placebo. Fundam Clin Pharmacol 1997;11:127-32. View abstract.

Bracken MB, Triche EW, Belanger K, et al. Association of maternal caffeine consumption with decrements in fetal growth. Am J Epidemiol 2003;157:456-66.. View abstract.

Breum L, Pedersen JK, Ahlstrom F, et al. Comparison of an ephedrine/caffeine combination and dexfenfluramine in the treatment of obesity. A double-blind multi-centre trial in general practice. Int J Obes Relat Metab Disord 1994;18:99-103. View abstract.

Briggs GB, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.

Brown NJ, Ryder D, Branch RA. A pharmacodynamic interaction between caffeine and phenylpropanolamine. Clin Pharmacol Ther 1991;50:363-71. View abstract.

Cannon ME, Cooke CT, McCarthy JS. Caffeine-induced cardiac arrhythmia: an unrecognised danger of healthfood products. Med J Aust 2001;174:520-1. View abstract.

Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. View abstract.

Carrillo JA, Benitez J. Clinically significant pharmacokinetic interactions between dietary caffeine and medications. Clin Pharmacokinet 2000;39:127-53. View abstract.

Chen JF, Xu K, Petzer JP, et al. Neuroprotection by caffeine and A(2A) adenosine receptor inactivation in a model of Parkinson's disease. J Neurosci 2001;21:RC143.. View abstract.

Chiu KM. Efficacy of calcium supplements on bone mass in postmenopausal women. J Gerontol A Biol Sci Med Sci 1999;54:M275-80. View abstract.

Chou T. Wake up and smell the coffee. Caffeine, coffee, and the medical consequences. West J Med 1992;157:544-53. View abstract.

Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32. View abstract.

Dews PB, O'Brien CP, Bergman J. Caffeine: behavioral effects of withdrawal and related issues. Food Chem Toxicol 2002;40:1257-61. View abstract.

DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.

Donadio V, Bonsi P, Zele I, et al. Myoglobinuria after ingestion of extracts of guarana, Ginkgo biloba and kava. Ginkgo biloba and kava. Neurol Sci 2000;21:124. View abstract.

Dreher HM. The effect of caffeine reduction on sleep quality and well-being in persons with HIV. J Psychosom Res 2003;54:191-8.. View abstract.

Electronic Code of Federal Regulations. Title 21. Part 182 -- Substances Generally Recognized As Safe. Available at:

Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9. View abstract.

FDA. Proposed rule: dietary supplements containing ephedrine alkaloids. Available at: (Accessed 25 January 2000).

Fernandes O, Sabharwal M, Smiley T, et al. Moderate to heavy caffeine consumption during pregnancy and relationship to spontaneous abortion and abnormal fetal growth: a meta-analysis. Reprod Toxicol 1998;12:435-44. View abstract.

Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4. View abstract.

For Dieter, Nearly the Ultimate Loss. The Washington Post. Available at: (Accessed 19 March 2000).

Forrest WH Jr, Bellville JW, Brown BW Jr. The interaction of caffeine with pentobarbital as a nighttime hypnotic. Anesthesiology 1972;36:37-41. View abstract.

Grandjean AC, Reimers KJ, Bannick KE, Haven MC. The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration. J Am Coll Nutr 2000;19:591-600.. View abstract.

Greenway FL, Raum WJ, DeLany JP. The effect of an herbal dietary supplement containing ephedrine and caffeine on oxygen consumption in humans. J Altern Complement Med 2000;6:553-5. View abstract.

Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63. View abstract.

Haller CA, Benowitz NL, Jacob P 3rd. Hemodynamic effects of ephedra-free weight-loss supplements in humans. Am J Med 2005;118:998-1003.. View abstract.

Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000;343:1833-8. View abstract.

Haller CA, Jacob P 3rd, Benowitz NL. Pharmacology of ephedra alkaloids and caffeine after single-dose dietary supplement use. Clin Pharmacol Ther 2002;71:421-32. View abstract.

Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. View abstract.

Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. View abstract.

Heseltine D, Dakkak M, woodhouse K, et al. The effect of caffeine on postprandial hypotension in the elderly. J Am Geriatr Soc 1991;39:160-4. View abstract.

Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. View abstract.

Holmgren P, Norden-Pettersson L, Ahlner J. Caffeine fatalities--four case reports. Forensic Sci Int 2004;139:71-3. View abstract.

Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80. View abstract.

Howell LL, Coffin VL, Spealman RD. Behavioral and physiological effects of xanthines in nonhuman primates. Psychopharmacology (Berl) 1997;129:1-14. View abstract.

Infante S, Baeza ML, Calvo M, et al. Anaphylaxis due to caffeine. Allergy 2003;58:681-2. View abstract.

Institute of Medicine. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington, DC: National Academy Press, 2001. Available at:

Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3. View abstract.

Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9. View abstract.

Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl) 2004;176:1-29. View abstract.

Kamimori GH, Penetar DM, Headley DB, et al. Effect of three caffeine doses on plasma catecholamines and alertness during prolonged wakefulness. Eur J Clin Pharmacol 2000;56:537-44.. View abstract.

Keijzers GB, De Galan BE, Tack CJ, et al. Caffeine can decrease insulin sensitivity in humans. Diabetes Care. 2002 Feb;25:364-9. View abstract.

Klebanoff MA, Levine RJ, DerSimonian R, et al. Maternal serum paraxanthine, a caffeine metabolite, and the risk of spontaneous abortion. N Engl J Med 1999;341:1639-44. View abstract.

Kleemola P, Jousilahti P, Pietinen P, et al. Coffee consumption and the risk of coronary heart disease and death. Arch Intern Med 2000;160:3393-400.. View abstract.

Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. View abstract.

Kynast-Gales SA, Massey LK. Effect of caffeine on circadian excretion of urinary calcium and magnesium. J Am Coll Nutr. 1994;13:467-72. View abstract.

Lake CR, Rosenberg DB, Gallant S, et al. Phenylpropanolamine increases plasma caffeine levels. Clin Pharmacol Ther 1990;47:675-85. View abstract.

Lane JD, Barkauskas CE, Surwit RS, Feinglos MN. Caffeine impairs glucose metabolism in type 2 diabetes. Diabetes Care 2004;27:2047-8. View abstract.

Leson CL, McGuigan MA, Bryson SM. Caffeine overdose in an adolescent male. J Toxicol Clin Toxicol 1988;26:407-15. View abstract.

Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61. View abstract.

Mansi IA, Huang J. Rhabdomyolysis in response to weight-loss herbal medicine. Am J Med Sci 2004;327:356-357. View abstract.

Massey LK, Whiting SJ. Caffeine, urinary calcium, calcium metabolism and bone. J Nutr 1993;123:1611-4. View abstract.

Massey LK. Is caffeine a risk factor for bone loss in the elderly? Am J Clin Nutr 2001;74:569-70. View abstract.

May DC, Jarboe CH, VanBakel AB, Williams WM. Effects of cimetidine on caffeine disposition in smokers and nonsmokers. Clin Pharmacol Ther 1982;31:656-61. View abstract.

McGowan JD, Altman RE, Kanto WP Jr. Neonatal withdrawal symptoms after chronic maternal ingestion of caffeine. South Med J 1988;81:1092-4.. View abstract.

Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. View abstract.

Nawrot P, Jordan S, Eastwood J, et al. Effects of caffeine on human health. Food Addit Contam 2003;20:1-30. View abstract.

Nehlig A, Debry G. Consequences on the newborn of chronic maternal consumption of coffee during gestation and lactation: a review. J Am Coll Nutr 1994;13:6-21.. View abstract.

Nix D, Zelenitsky S, Symonds W, et al. The effect of fluconazole on the pharmacokinetics of caffeine in young and elderly subjects. Clin Pharmacol Ther 1992;51:183.

Nurminen ML, Niittynen L, Korpela R, Vapaatalo H. Coffee, caffeine and blood pressure: a critical review. Eur J Clin Nutr 1999;53:831-9. View abstract.

Petrie HJ, Chown SE, Belfie LM, et al. Caffeine ingestion increases the insulin response to an oral-glucose-tolerance test in obese men before and after weight loss. Am J Clin Nutr 2004;80:22-8. View abstract.

Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. View abstract.

Raaska K, Raitasuo V, Laitila J, Neuvonen PJ. Effect of caffeine-containing versus decaffeinated coffee on serum clozapine concentrations in hospitalised patients. Basic Clin Pharmacol Toxicol 2004;94:13-8. View abstract.

Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700. View abstract.

Rees K, Allen D, Lader M. The influences of age and caffeine on psychomotor and cognitive function. Psychopharmacology (Berl) 1999;145:181-8. View abstract.

Robinson LE, Savani S, Battram DS, et al. Caffeine ingestion before an oral glucose tolerance test impairs blood glucose management in men with type 2 diabetes. J Nutr 2004;134:2528-33. View abstract.

Ross GW, Abbott RD, Petrovitch H, et al. Association of coffee and caffeine intake with the risk of parkinson disease. JAMA 2000;283:2674-9. View abstract.

Sanderink GJ, Bournique B, Stevens J, et al. Involvement of human CYP1A isoenzymes in the metabolism and drug interactions of riluzole in vitro. Pharmacol Exp Ther 1997;282:1465-72. View abstract.

Savitz DA, Chan RL, Herring AH, et al. Caffeine and miscarriage risk. Epidemiology 2008;19:55-62. View abstract.

Schechter MD, Timmons GD. Objectively measured hyperactivity--II. Caffeine and amphetamine effects. J Clin Pharmacol 1985;25:276-80.. View abstract.

Sinclair CJ, Geiger JD. Caffeine use in sports. A pharmacological review. J Sports Med Phys Fitness 2000;40:71-9. View abstract.

Smith A. Effects of caffeine on human behavior. Food Chem Toxicol 2002;40:1243-55. View abstract.

Spinella M. Herbal Medicines and Epilepsy: The Potential for Benefit and Adverse Effects. Epilepsy Behav 2001;2(6):524-532. View abstract.

Stanek EJ, Melko GP, Charland SL. Xanthine interference with dipyridamole-thallium-201 myocardial imaging. Pharmacother 1995;29:425-7. View abstract.

Stookey JD. The diuretic effects of alcohol and caffeine and total water intake misclassification. Eur J Epidemiol 1999;15:181-8. View abstract.

Suleman A, Siddiqui NH. Haemodynamic and cardiovascular effects of caffeine. Medicine On Line Int J Medicine 2000. (Accessed 14 April 2000).

The National Toxicology Program (NTP). Caffeine. Center for the Evaluation of Risks to Human Reproduction (CERHR). Available at:

Tobias JD. Caffeine in the treatment of apnea associated with respiratory syncytial virus infection in neonates and infants. South Med J 2000;93:297-304. View abstract.

Underwood DA. Which medications should be held before a pharmacologic or exercise stress test? Cleve Clin J Med 2002;69:449-50. View abstract.

Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3. View abstract.

Vandeberghe K, Gillis N, Van Leemputte M, et al. Caffeine counteracts the ergogenic action of muscle creatine loading. J Appl Physiol 1996;80:452-7. View abstract.

Wahllander A, Paumgartner G. Effect of ketoconazole and terbinafine on the pharmacokinetics of caffeine in healthy volunteers. Eur J Clin Pharmacol 1989;37:279-83. View abstract.

Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. View abstract.

Wallach J. Interpretation of Diagnostic Tests. A synopsis of Laboratory Medicine. Fifth ed; Boston, MA: Little Brown, 1992.

Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. View abstract.

Watson JM, Sherwin RS, Deary IJ, et al. Dissociation of augmented physiological, hormonal and cognitive responses to hypoglycaemia with sustained caffeine use. Clin Sci (Lond) 2003;104:447-54. View abstract.

Wemple RD, Lamb DR, McKeever KH. Caffeine vs caffeine-free sports drinks: effects on urine production at rest and during prolonged exercise. Int J Sports Med 1997;18:40-6. View abstract.

Weng X, Odouli R, Li DK. Maternal caffeine consumption during pregnancy and the risk of miscarriage: a prospective cohort study. Am J Obstet Gynecol 2008;198:279.e1-8. View abstract.

Williams MH, Branch JD. Creatine supplementation and exercise performance: an update. J Am Coll Nutr 1998;17:216-34. View abstract.

Winkelmayer WC, Stampfer MJ, Willett WC, Curhan GC. Habitual caffeine intake and the risk of hypertension in women. JAMA 2005;294:2330-5. View abstract.

Zheng XM, Williams RC. Serum caffeine levels after 24-hour abstention: clinical implications on dipyridamole (201)Tl myocardial perfusion imaging. J Nucl Med Technol 2002;30:123-7. View abstract.

Health Solutions From Our Sponsors