Approximately 16 percent of Americans between the ages of 14 and 49 are infected with herpes simplex type 2. Most are asymptomatic, and 90 percent of the infected are unaware of their status. Nearly 25 percent of the U.S. population will be exposed to HSV-2 by the time they reach 40. Symptoms of HSV-2 include sore, painful genital lesions, flulike symptoms, and fatigue. Clinical research has assessed the efficacy of the amino acid supplement L-lysine, or simply lysine, in helping to alleviate the duration and severity of HSV-2 symptoms.
Pathophysiology of HSV-2
Herpes simplex type 2 is an incurable, highly contagious, sexually transmitted virus that affects the genitalia and possibly the buttock region. In most cases HSV-2 is sub-clinical and asymptomatic, but 20 percent of patients experience recurrent symptoms that can last from 2 to 14 days. Infected people who do not experience symptoms may shed the virus intermittently and inadvertantly pass the infection to others.
Lysine Supplementation and HSV-2
Lysine has been studied as a preventative and treatment for recurrent HSV-2. A double-blind, placebo-controlled trial consisting of 51 study participants with recurrent, symptomatic HSV-2 showed that 1,000 mg of L-lysine taken three times daily shortened the length of the episode and decreased severity of outbreaks. Additionally, patients experienced 2 to 4 fewer outbreaks on average over the course of the study than patients given a placebo. A similar study showed 1,248 mg of lysine was effective in decreasing the number of recurrent infections but not in decreasing the healing time of herpes lesions.
Safety of Lysine Supplementation
Although lysine is an essential amino acid, the safety of ingesting mega-doses of supplements for long-term periods has not been assessed. The current dietary reference intake for lysine, established by the National Institute of Medicine, is 21 mg per pound of body weight in adults.
Best Course of Action
Lysine has been proved in clinical trials to have a positive effect on the recurrence of HSV-2 outbreaks. However, the prescription medications acyclovir and valacyclovir are the best treatments for shortening HSV-2 reactivation episodes and decreasing associated symptoms. Before you decide to start taking large doses of lysine for the treatment or prevention of HSV-2, consult your doctor.
References
- "Dermatology"; Success of L-lysine Therapy in Frequently Recurrent Herpes Simplex Infection; R.S. Griffith et al.; January 1987
- "Cutis"; Treatment of Recurrent Herpes Simplex Infections with L-Lysine Monohydrochloride; M.A. McCune et al.; October 1984
- "Acta Dermato Venereologica"; Lysine Prophylaxis in Recurrent Herpes Simplex Labilatis: A Double-Blind, Controlled Crossover Study; N. Milman et al.; 1980
- "New England Journal of Medicine"; Reactivation of Genital Herpes Simplex Virus Type 2 in Asymptomatic Seropositive Persons; A. Walk et al.; March 2000
- "Journal of the American Medical Association"; National Trends in Herpes Simplex Virus Type 1 and Type 2 in the United States: Data from the National Health and Nutrition Examination Survey; F. Xu et al.; August 2006
- "Journal of the American College of Nutrition"; The Metabolic Roles, Pharmacology, and Toxicology of Lysine; N.W. Flodin; 1997
