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L-citrulline

What other names is L-citrulline known by?

2-amino-5-(carbamoylamino)pentanoic acid, Citrulline, Citrulline Malate, L-Citrulina, L-Citrulline AKG, L-Citrulline-Alpha Ketoglutaric Acid, L-Citrulline Malate, Malate de Citrulline.

What is L-citrulline?

L-citrulline is a naturally occurring amino acid. It is found in some foods like watermelons and is also produced naturally by the body.

L-citrulline is used for Alzheimer's disease, dementia, fatigue, muscle weakness, sickle cell disease, erectile dysfunction, high blood pressure, and diabetes. It is used for heart disease, body building, increasing energy, and for improving athletic performance.

Insufficient Evidence to Rate Effectiveness for...

  • Exercise performance. L-citrulline might not be effective for improving exercise performance. In one research test, L-citrulline did not improve performance on a treadmill. People who took L-citrulline actually became exhausted more quickly than people who did not take it.
  • High blood pressure in children after heart surgery. L-citrulline might help reduce the high blood pressure that can occur after heart surgery in children. It's given before and after the surgery.
  • Sickle cell disease. L-citrulline might improve some symptoms in people with sickle cell disease.
  • Other conditions.
More evidence is needed to rate the effectiveness of L-citrulline for these uses.

How does L-citrulline work?

L-citrulline is a naturally occurring amino acid found in food, such as watermelons, and also made in the body. Our bodies change L-citrulline into another amino acid called L-arginine and also to nitric oxide. L-citrulline might help increase the supply of ingredients the body needs to making certain proteins. It might also help open up veins and arteries to improve blood flow and reduce blood pressure.

QUESTION

Next to red peppers, you can get the most vitamin C from ________________. See Answer

Are there safety concerns?

L-citrulline is POSSIBLY SAFE when used appropriately by adults and children.

Special Precautions & Warnings:

Pregnancy or breast-feeding: There is not enough reliable scientific information to know if L-citrulline is safe to take during pregnancy or while breast-feeding. Until more is known, avoid L-citrulline while you are pregnant or breast-feeding.

Are there any interactions with medications?


Medications for male sexual dysfunction (Phosphodiesterase-5 Inhibitors)Interaction Rating: Major Do not take this combination.

L-citrulline might decrease blood pressure. Some medications for male sexual dysfunction can also decrease blood pressure. Taking L-citrulline along with medications for male sexual dysfunction might cause your blood pressure to go too low.

Some medications for male sexual dysfunction include sildenafil (Viagra), tadalafil (Cialis), and vardenafil (Levitra).


Medications that increase blood flow to the heart (Nitrates)Interaction Rating: Major Do not take this combination.

L-citrulline might decrease blood pressure and increase blood flow. Taking L-citrulline with other medications that increase blood flow to the heart might increase the chance of dizziness and lightheadedness.

Some of these medications that increase blood flow to the heart include nitroglycerin (Nitro-Bid, Nitro-Dur, Nitrostat) and isosorbide (Imdur, Isordil, Sorbitrate).


Medications for high blood pressure (Antihypertensive drugs)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

L-citrulline might decrease blood pressure. Taking L-citrulline along with medications for high blood pressure might cause your blood pressure to go too low.

Some medications for high blood pressure include captopril (Capoten), enalapril (Vasotec), losartan (Cozaar), valsartan (Diovan), diltiazem (Cardizem), Amlodipine (Norvasc), hydrochlorothiazide (HydroDIURIL), furosemide (Lasix), and many others.

Dosing considerations for L-citrulline.

The appropriate dose of L-citrulline 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 L-citrulline. 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.

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).

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Reviewed on 9/17/2019
References

Barr FE, Tirona RG, Taylor MB, et al. Pharmacokinetics and safety of intravenously administered citrulline in children undergoing congenital heart surgery: potential therapy for postoperative pulmonary hypertension. J Thorac Cardiovasc Surg 2007;134:319-26. View abstract.

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Carpenter TO, Levy HL, Holtrop ME, et al. Lysinuric protein intolerance presenting as childhood osteoporosis. Clinical and skeletal response to citrulline therapy. New Engl J Med 1985;312:290-4. View abstract.

Collins JK, Wu G, Perkins-Veazie P, et al. Watermelon consumption increases plasma arginine concentrations in adults. Nutrition 2007;23:261-6. View abstract.

Curis E, Nicolis I, Moinard C, et al. Almost all about citrulline in mammals. Amino Acids 2005;29:177-205. View abstract.

Hayashi T, Juliet PAR, Matsui-Hirai H, et al. L-citrulline and L-arginine supplementation retards the progression of high-cholesterol-diet-induced atherosclerosis in rabbits. Proc Natl Acad Sci U S A 2005;102:13681-6. View abstract.

Hickner RC, Tanner CJ, Evans CA, et al. L-citrulline reduces time to exhaustion and insulin response to a graded exercise test. Med Sci Sports Exerc 2006;38:660-6. View abstract.

Mandel H, Levy N, Izkovitch S, Korman SH. Elevated plasma citrulline and arginine due to consumption of Citrullus vulgaris (watermelon). J Inherit Metab Dis 2005;28:467-72. View abstract.

Moinard C, Nicolis I, Neveux N, et al. Dose-ranging effects of citrulline administration on plasma amino acids and hormonal patterns in healthy subjects: the Citrudose pharmacokinetic study. Br J Nutr 2008;99:855-62. View abstract.

Osowska S, Duchemann T, Walrand S, et al. Citrulline modulates muscle protein metabolism in old malnourished rats. Am J Physiol Endocrinol Metab 2006;291:E582-6. View abstract.

Osowska S, Moinard C, Neveux N, et al. Citrulline increases arginine pools and restores nitrogen balance after massive intestinal resection. Gut 2004;53:1781-6. View abstract.

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Ruiz E, Del Rio M, Somoza B, et al. L-citrulline, the by-product of nitric oxide synthesis, decreases vascular smooth muscle cell proliferation. J Pharmacol Exp Therap 1999;290:310-3. View abstract.

Ruiz E, Tejerina T. Relaxant effects of L-citrulline in rabbit vascular smooth muscle. Br J Pharmacol 1998;125:186-92. View abstract.

Schwedhelm E, Maas R, Freese R, et al. Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. Br J Clin Pharmacol 2008;65:51-9. View abstract.

Smith HA, Canter JA, Christian KG, et al. Nitric oxide precursors and congenital heart surgery: a randomized controlled trial of oral citrulline. J Thorac Cardiovasc Surg 2006;132:58-65. View abstract.

Tremblay GC. Ornithine or citrulline therapy in treatment of Reye's syndrome (letter). New Engl J Med 1975;292:160-1. View abstract.

Waugh WH, Daeschner CW 3rd, Files BA, et al. Oral citrulline as arginine precursor may be beneficial in sickle cell disease: early phase two results. J Natl Med Assoc 2001;93:363-71. View abstract.

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