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Caffeine

IN THIS ARTICLE

Are there any interactions with medications?



Ephedrine
Interaction Rating: Major Do not take this combination.

Stimulant drugs speed up the nervous system. Caffeine and ephedrine are both stimulant drugs. Taking caffeine 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.

Caffeine might block the effects 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 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 caffeine 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).



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

Carbamazepine is used to treat some seizures. Caffeine may lower the effects of carbamazepine or increase how susceptible a person is to seizures. In theory, taking caffeine with carbamazepine can reduce its effects and increase the risk of seizures in some people.



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

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 caffeine 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. Caffeine seems to decrease how quickly the body breaks down clozapine (Clozaril). Taking caffeine 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.

Caffeine might block the affects 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 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 caffeine along with disulfiram (Antabuse) might increase the effects and side effects of caffeine including jitteriness, hyperactivity, irritability, and others.



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

The body breaks down caffeine to get rid of it. Estrogens can decrease how quickly the body breaks down caffeine. Taking caffeine along with estrogens might 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.



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

Ethnosuximide is used to control certain types of seizures. Caffeine might lower the effects of ethnosuximide or increase how susceptible a person is to seizures. In theory, taking caffeine with ethnosuximide might reduce its effects and increase the risk of seizures.



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

Felbamate is used to control certain types of seizures. Caffeine might lower the effects of felbamate or increase how susceptible a person is to seizures. In theory, taking caffeine with felbamate might reduce its effects and increase the risk of seizures.



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

The body breaks down flutamide (Eulexin) to get rid of it. Caffeine might decrease how quickly the body breaks down flutamide (Eulexin). Taking caffeine along with flutamide (Eulexin) might cause too much flutamide (Eulexin) in the body, and increase the risk of side effects of flutamide (Eulexin).



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

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



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

You body naturally gets rid of lithium. Caffeine 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.

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.

Caffeine can stimulate the body. Some medications used for depression can also stimulate the body. Taking caffeine along with some medications 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.

Caffeine might slow blood clotting. Taking caffeine along with medications that also slow clotting might increase the chances of bruising and bleeding in some people.

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.



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

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



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

Phenobarbital is used to control some types of seizures. Caffeine might lower the effects of phenobarbital or increase how susceptible a person is to seizures. In theory, taking caffeine with phenobarbital might reduce its effects and increase the risk of seizures.



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

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



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

Phenytoin is used to control some types of seizures. Caffeine might lower the effects of phenytoin or increase how susceptible a person is to seizures. In theory, taking caffeine with phenytoin might reduce its effects and increase the risk of seizures.



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 caffeine along with riluzole (Rilutek) might decrease how fast the body breaks down riluzole (Rilutek) and increase the effects and side effects of riluzole (Rilutek).



Stimulant drugs
Interaction 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 heart rate. Caffeine might also speed up the nervous system. Taking caffeine along with stimulant drugs might cause serious problems including increased heart rate and high blood pressure. Avoid taking stimulant drugs along with caffeine.

Some stimulant drugs include diethylpropion (Tenuate), epinephrine, phentermine (Ionamin), pseudoephedrine (Sudafed), and many others.



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

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



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

Valproate is used to control some types of seizures. Caffeine can lower the effects of valproate or increase how susceptible a person is to seizures. In theory, taking caffeine with valproate might reduce its effects and increase the risk of seizures.



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

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



Water pills (Diuretic drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.

Caffeine can reduce potassium levels. "Water pills" can also decrease potassium levels in the body. Taking caffeine with water pills might cause potassium levels to drop too low.

Some "water pills" that can deplete potassium include chlorothiazide (Diuril), chlorthalidone (Thalitone), furosemide (Lasix), hydrochlorothiazide (HCTZ, HydroDiuril, Microzide), and others.



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

The body breaks down caffeine to get rid of it. Alcohol can decrease how quickly the body breaks down caffeine. Taking caffeine 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 caffeine to get rid of it. Birth control pills can decrease how quickly the body breaks down caffeine. Taking caffeine 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.

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



Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates)
Interaction Rating: Minor Be cautious with this combination.
Talk with your health provider.

Caffeine is changed and broken down by the liver. Some drugs decrease how quickly the liver changes and breaks down certain medications and supplements. Taking caffeine along with these drugs might slow the processing of caffeine and increase caffeine levels.

Some of these medications that affect the liver include fluvoxamine, mexiletine, clozapine, psoralens, furafylline, theophylline, idrocilamide, and others.



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

Caffeine might increase or decrease blood sugar. Diabetes medications are used to lower blood sugar. Taking caffeine with some medications for diabetes might increase or decrease the effectiveness of the 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.



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

The body breaks down caffeine to get rid of it. Metformin can decrease how quickly the body breaks down caffeine. Taking metformin along with caffeine might increase the effects and side effects of caffeine.



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

The body breaks down caffeine to get rid of it. Methoxsalen can decrease how quickly the body breaks down caffeine. Taking methoxsalen along with caffeine might increase the effects and side effects of caffeine.



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

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 caffeine might increase the effects and side effects of caffeine.



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

The body breaks down caffeine to get rid of it. Phenothiazines can decrease how quickly the body breaks down caffeine. Taking phenothiazines along with caffeine might increase the effects and side effects of caffeine.



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

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



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

Tiagabine is used to control some types of seizures. Caffeine does not seem to influence the effects of tiagabine. However, long-term caffeine use might increase blood levels of tiagbine.



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

The body breaks down caffeine to get rid of it. Ticlopidine (Ticlid) can decrease how fast the body gets rid of caffeine. Taking caffeine along with ticlopidine (Ticlid) can increase the risk of caffeine side effects.

Dosing considerations for Caffeine.

The following doses have been studied in scientific research:

BY MOUTH:
  • For headache or improving mental alertness: 250 mg per day.
  • For tiredness: 150-600 mg.
  • For improving athletic performance: 2-10 mg/kg or more has been used. However, doses in excess of 800 mg per day can result in urine levels greater than the 15 mcg/mL allowed by the National Collegiate Athletic Association.
  • For weight loss: the ephedrine/caffeine combination products are commonly dosed 20 mg/200 mg three times per day.
  • For headache after epidural anesthesia: 300 mg.
  • For preventing gallstone disease: intake of 400 mg or more of caffeine per day.
  • For preventing Parkinson's disease: men drinking 421-2716 mg of total caffeine daily have the lowest risk of developing Parkinson's disease, when compared to other men. However, men who drink as little as 124-208 mg of caffeine daily also have a significantly lower chance of developing Parkinson's disease. In women, moderate caffeine intake per day (1-3 cups of coffee per day) seems to be best.
One cup of brewed coffee provides from 95-200 mg of caffeine. An 8-ounce serving of black tea provides from 40-120 mg of caffeine. An 8-ounce serving of green tea provides 15-60 mg of caffeine. Soft drinks such as cola provide from 20-80 mg of caffeine per 12 ounce serving. Sports or energy drinks typically provide from 48-300 mg of caffeine per serving.

INTRAVENOUS:
  • Caffeine is given intravenously (by IV) by healthcare providers for breathing problems in infants and for headache after epidural anesthesia.

Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.

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Report Problems to the Food and Drug Administration

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.





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