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Headache, Migraine
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Look Up > Supplements > Lysine
Dietary Sources
Commercial Preparations
Therapeutic Uses
Dosage Ranges and Duration of Administration
Side Effects/Toxicology


Lysine is an essential amino acid that is not synthesized in adequate amounts by the body, so it must be obtained from dietary sources. Lysine furnishes the structural components for the synthesis of carnitine, which promotes fatty acid synthesis within the cell. It is particularly important for proper growth. Lysine also regulates calcium absorption and plays an important role in the formation of collagen.

A vegetarian diet may not provide sufficient lysine. Among protein sources, plants often contain insufficient sources of lysine. Lysine is the limiting amino acid of many cereals. In many areas of the world where diets are grain-based, this becomes important as a lysine deficiency can create a negative nitrogen balance and lead to kidney stones. Lysine deficiency may be characterized by fatigue, nausea, dizziness, appetite loss, emotional agitation, decreased antibody formation, decreased immunity, slow growth, anemia, reproductive disorders, pneumonia, acidosis, and bloodshot eyes.

Lysine has been used to treat herpes infections caused by both herpes simplex viruses and herpes zoster. Supplementation can improve recovery speed and suppress recurrences of infections. Some studies have found lysine of potential benefit in treating cardiovascular disease, osteoporosis, asthma, migraines, nasal polyps, and postepisiotomy pain.

Dietary Sources

Generally, lysine is found in the following foods:

  • Meat, particularly red meats
  • Cheeses
  • Poultry
  • Sardines
  • Nuts
  • Eggs
  • Soybeans

The most concentrated sources are torula yeast, dried and salted cod, soybean protein isolate, soybean protein concentrate, Parmesan cheese, pork loin (excluding fat), dried and frozen tofu, freeze-dried parsley, defatted and low-fat soybean flour, fenugreek seed, and dried spirulina seaweed.


Lysine is an essential amino acid. Chemically, lysine is unique among the amino acids in that it possesses two amino (NH2) groups. The extra amino group can react with other substances, such as glucose or lactose, creating an amino–sugar complex that cannot be split by digestive enzymes, thus reducing the availability of lysine.

Lysine is also known as LYS, amino acid K, and 2-diamino-hexaenoic acid. Its chemical composition is C6H13NO2.

Commercial Preparations
  • L-lysine acetylsalicylate (LAS)
  • Lysine clonixinate (LC)
  • L-lysine monohydrochlorine (LMH)

Therapeutic Uses
  • Asthma: LAS, when administered by inhalation, has been shown to protect against histamine-induced bronchoconstriction.
  • Herpes: Supplementation may improve recovery speed and suppress recurrences of infections.
  • Migraine: Treatment with a combination of LAS and metoclopramide may be effective.
  • Nasal polyps: Recent research suggests that LAS may prevent relapses of nasal polyps.
  • Postepisiotomy pain: 125 mg/day of LC was found to reduce postepisiotomy pain in primiparous patients with moderate to severe postepisiotomy pain.

Dosage Ranges and Duration of Administration

The following are the recommended dietary allowances, according to the National Research Council.

  • Birth to 4 months: 103 mg/kg/day
  • 5 months to 2 years: 69 mg/kg/day
  • 3 to 12 years: 44 mg/kg/day
  • Adults and teenagers: 12 mg/kg/day

Based on obligatory amino acid losses (including data from amino acid tracer studies), it has been suggested that adults need 30 mg/kg/day.

Nutritional doses are 1 to 3 g per day.

Side Effects/Toxicology

Lysine appears to be nontoxic.


L-lysine may increase cholesterol and triglyceride levels.


No clinically significant interactions between lysine and conventional medications are known to have been reported in the literature to date.


Bruzzese N, Sica G, Iacopino F, et al. Growth inhibition of fibroblasts from nasal polyps and normal skin by lysine acetylsalicylate. Allergy. 1998;53:431-434.

De los Santos AR, Marti MI, Espinosa D, Di Girolamo G, Vinacur JC, Casadei A. Lysine clonixinate vs. paracetamol/codeine in postepisiotomy pain. Acta Physiol Pharmacol Ther Latinoam. 1998;48(1):52-58.

Ensminger AH, Ensminger ME, Konlande JE, Robson JRK. Foods & Nutrition Encyclopedia. 2nd ed. Boca Raton, Fla: CRC Press, Inc; 1994:60-64, 1748.

Flodin NW. The metabolic roles, pharmacology, and toxicology of lysine. J Am Coll Nutr. 1997;16:7-21.

Garrison RH Jr, Somer E. The Nutrition Desk Reference. 3rd ed. New Canaan, Conn: Keats Publishing, Inc; 1995:39-52.

Haas EM. Staying Healthy with Nutrition. Berkeley, Calif: Celestial Arts Publishing; 1992.

Hugues FC, Lacoste JP, Danchot J, Joire JE. Repeated doses of combined oral lysine acetylsalicylate and metoclopramide in the acute treatment of migraine. Headache. 1997;37:452-454.

Newstrom H. Nutrients Catalog. Jefferson, NC: McFarland & Co; 1993:303-312.

Shils ME, Olson JA, Shike M, Ross AC. Modern Nutrition in Health and Disease. 9th ed. Baltimore, Md: Williams & Wilkins; 1999:41, 1010.

Werbach MR. Nutritional Influences on Illness. 2nd ed. Tarzana, Calif: Third Line Press; 1993:159-160, 384, 434, 494-495, 506, 580, 613-614, 636.

Copyright © 2000 Integrative Medicine Communications

This publication contains information relating to general principles of medical care that should not in any event be construed as specific instructions for individual patients. The publisher does not accept any responsibility for the accuracy of the information or the consequences arising from the application, use, or misuse of any of the information contained herein, including any injury and/or damage to any person or property as a matter of product liability, negligence, or otherwise. No warranty, expressed or implied, is made in regard to the contents of this material. No claims or endorsements are made for any drugs or compounds currently marketed or in investigative use. The reader is advised to check product information (including package inserts) for changes and new information regarding dosage, precautions, warnings, interactions, and contraindications before administering any drug, herb, or supplement discussed herein.