Arginine (L-Arginine) : Dosing, Safety, Interactions

by MedlinePlus

(Page 3 of 3)

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Standardization:

Intravenous arginine hydrochloride is available as a 10% solution (950 mOsm/L), with 47.5mEq chloride ion per 100mL. There is no established standardization for oral arginine products.

Note: Most people likely do not need to take arginine supplements because the body usually makes sufficient amounts.

Adults (18 years and older):

Tablets/capsules: There are no standard or well-established doses of arginine, and many different doses have been used and studied. A dose that has been studied for treating coronary artery disease is two to three grams taken by mouth three times daily for three to six months. A studied dose for heart failure is 5.6 to 12.6 grams taken by mouth every day, divided into two or three equal doses, taken for six weeks. For erectile dysfunction, 1.6 grams taken by mouth three times daily for six weeks has been studied. For low sperm count, four grams daily for three months has been used. For women undergoing in vitro (test tube) fertilization, a dose of 16 grams daily by mouth has been studied, although this therapy should be discussed with the healthcare provider coordinating the in vitro program. For interstitial cystitis, 500 milligrams taken by mouth three times daily for six weeks has been used. For the long-term management of inborn disorders of the urea cycle, doses between 0.5 to 2 grams daily have been used. 8.5 grams of arginine daily has been studied in patients with pressure ulcers for 4 weeks.

Intravenous: Doses of arginine used intravenously depend on specific institutional dosing guidelines and should be given under the supervision of a healthcare provider.

Children (younger than 18 years):

Arginine supplements are not recommended in children because there is not enough scientific information available and because of potential side effects.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

Anaphylaxis (severe allergic reaction) has occurred after arginine injections. People with a known allergy should avoid arginine. Signs of allergy may include rash, itching or shortness of breath.

Side Effects and Warnings

Arginine has been well tolerated by most people in studies lasting for up to six months, although there is a possibility of serious adverse effects in some individuals.

Stomach discomfort, including nausea, stomach cramps or an increased number of stools, may occur. People with asthma may experience a worsening of symptoms if arginine is inhaled, which may be related to allergy.

Other potential side effects include low blood pressure and changes in numerous chemicals and electrolytes in the blood. Examples include high potassium, high chloride, low sodium, low phosphate, high blood urea nitrogen and high creatinine levels. People with liver or kidney disease may be especially sensitive to these complications and should avoid using arginine except under medical supervision. After injections of arginine, low back pain, flushing, headache, numbness, restless legs, venous irritation and death of surrounding tissues have been reported.

In theory, arginine may increase the risk of bleeding. Patients using anticoagulants (blood thinners) or antiplatelet drugs, or with underlying bleeding disorders, should speak with a qualified healthcare provider before using arginine and should be monitored.

Arginine may increase blood sugar levels. Caution is advised in patients taking prescription drugs to control sugar levels.

Pregnancy and Breastfeeding

Arginine cannot be recommended as a supplement during pregnancy and breast-feeding because there is not enough scientific information available.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Interactions with Drugs Because arginine can increase the activity of some hormones in the body, many possible drug interactions may occur. The prescription drugs aminophylline and the sweetening agent xylitol can decrease the effect that arginine has on glucagon.

Estrogens (found in birth control pills and hormone replacement therapies) may increase the effects of arginine on growth hormone, glucagon and insulin. In contrast, progestins (also found in birth control pills and some hormone replacement therapies) may decrease the responsiveness of growth hormone to arginine.

When used with arginine, some diuretics such as spironolactone (Aldactone®) or ACE-inhibitor blood pressure drugs such as enalapril (Vasotec®) may cause potassium levels in the blood to get too high. Monitoring of blood potassium levels may be required.

Arginine should be used carefully with drugs such as nitroglycerin or sildenafil (Viagra®) because blood pressure may fall too low. Other adverse effects such as headache and flushing may occur when arginine is used with these drugs.

Because arginine may cause the stomach to make more acid, it may reduce the effectiveness of drugs that block stomach acid such as ranitidine (Zantac®) or esomeprazole (Nexium®).

In theory, arginine may increase the risk of bleeding when used with anticoagulants (blood thinners) or antiplatelet drugs. Examples include warfarin (Coumadin®), heparin and clopidogrel (Plavix®). Some pain relievers may also increase the risk of bleeding if used with arginine. Examples include aspirin, ibuprofen (Motrin®, Advil®) and naproxen (Naprosyn®, Aleve®, Anaprox®).

It is also possible that arginine may raise blood sugar levels. Patients taking oral drugs for diabetes or using insulin should be monitored closely by their health care provider while using arginine. Dosing adjustments may be necessary.

Studies suggest that a combination of ibuprofen and arginine (ibuprofen-arginate/Spedifen®) has a faster onset of pain relief than ibuprofen alone. Use of other ibuprofen-based pain relievers such as Motrin® or Advil® with ibuprofen-arginate may increase the risk of toxic effects. Patients should consult their healthcare provider before combining these medications.

Interactions with Herbs and Dietary Supplements

Arginine may block the benefits of lysine in treating cold sores. It may increase the activity of growth hormone if used with ornithine.

In theory, arginine may increase the risk of bleeding when taken with herbs and supplements that are believed to increase the risk of bleeding. Multiple cases of bleeding have been reported with the use of Ginkgo biloba , and fewer cases with garlic and saw palmetto. Numerous other agents may theoretically increase the risk of bleeding, although this has not been proven in most cases. Some examples include: alfalfa, American ginseng, angelica, anise, Arnica montana , asafetida, aspen bark, bilberry, birch, black cohosh, bladderwrack, bogbean, boldo, borage seed oil, bromelain, capsicum, cat's claw, celery, chamomile, chaparral, clove, coleus, cordyceps, danshen, devil's claw, dong quai, EPA (eicosapentaenoic acid, found in fish oils), evening primrose oil, fenugreek, feverfew, fish oil, flaxseed/flax powder (not a concern with flaxseed oil), ginger, grapefruit juice, grapeseed, green tea, guggul, gymnestra, horse chestnut, horseradish, licorice root, lovage root, male fern, meadowsweet, nordihydroguairetic acid (NDGA), omega-3 fatty acids, onion, papain, panax ginseng, parsley, passionflower, poplar, prickly Ash, propolis, quassia, red clover, reishi, Siberian ginseng, sweet clover, rue, sweet birch, sweet clover, turmeric , vitamin E, white willow, wild carrot, wild lettuce, willow, wintergreen, and yucca.

Arginine may raise blood sugar levels. People using other herbs or supplements that may raise blood sugar levels such as cocoa, DHEA, ephedra (when combined with caffeine) or melatonin should be monitored closely by their healthcare provider while using arginine. Dosing adjustments may be necessary.

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