Can Lysine Help to Heal Cold Sores?

lysine for cold sores
Blend Images - Peathegee Inc/Brand X Pictures/Getty Images

Lysine supplements are touted as a natural remedy for a number of health problems, including cold sores (herpes simplex labialis), genital herpes, and shingles. Also known as "L-lysine," lysine is an essential amino acid thought to help the body produce infection-fighting antibodies, enzymes, hormones, and body tissues. Proponents claim that lysine supplements can also boost the immune system, as well as aid in muscle repair. Some lysine supplements contain a combination of lysine and L-arginine, another essential amino acid.

Research on Lysine Supplements

Although research on the use of lysine supplements is limited, some studies suggest that lysine supplements hold promise as a treatment for certain health conditions. Here's a look at a few key study findings:

1) Lysine for Cold Sores

Some studies suggest that lysine supplements may reduce the severity and duration of cold sore outbreaks by keeping the herpes simplex virus from replicating. In research studies, oral lysine is typically taken in doses of 1000-1248 mg per day. However, some clinical research suggests that lysine may not help. A 1984 study, published in Archives of Dermatology, explored the use of oral lysine supplements (400 mg, three times per day) in a group of 21 patients with recurrent herpes simplex infection but did not find a substantial benefit of lysine treatment for prevention or treatment. A 2015 analysis of randomized controlled trials of interventions for the prevention of herpes simplex labialis did not find any evidence for the effectiveness of lysine.

Topical application of a lysine ointment has also been explored for herpes simplex infections. In a 2005 study of 30 patients, for instance, scientists found that cold sores cleared up in 40 percent of participants after three days of using a lysine- and zinc oxide-based ointment (called Super Lysine Plus +) applied topically every two hours. By the sixth day of treatment, cold sore symptoms were resolved in 87 percent of patients. (When left untreated, cold sores may last up to 21 days.)

2) Anxiety

For a report published in 2010, researchers looked at 24 studies on the use of dietary supplements in the treatment of anxiety. Along with kava and passionflower, a combination of L-lysine and L-arginine was found to be one of the most effective supplements for anxiety relief. Earlier research shows that supplements containing a combination of L-lysine and L-arginine may help alleviate anxiety by normalizing certain hormones involved in the stress response.

3) Osteoporosis

Preliminary research in animals suggests that lysine supplements may increase the body's absorption of calcium and, in turn, protect against bone loss. However, scientists have yet to determine if lysine supplements can help prevent osteoporosis in humans.

Using Lysine Supplements for Health

Most people can get their fill of lysine by following a balanced diet containing high-protein foods (such as nuts, beans, eggs, and soy). If you're interested in using lysine supplements to treat or prevent a specific health problem, make sure to consult your physician before starting your supplement regimen.

Was this page helpful?
Article Sources
  • Chi CC1, Wang SH, Delamere FM, Wojnarowska F, Peters MC, Kanjirath PP. Interventions for prevention of herpes simplex labialis (cold sores on the lips). Cochrane Database Syst Rev. 2015 Aug 7;8:CD010095. [Epub ahead of print]
  • Civitelli R, Villareal DT, Agnusdei D, Nardi P, Avioli LV, Gennari C. "Dietary L-lysine and calcium metabolism in humans." Nutrition. 1992 Nov-Dec;8(6):400-5.
  • DiGiovanna JJ, Blank H. Failure of lysine in frequently recurrent herpes simplex infection. Treatment and prophylaxis. Arch Dermatol. 1984 Jan;120(1):48-51.
  • Fini M, Torricelli P, Giavaresi G, Carpi A, Nicolini A, Giardino R. "Effect of L-lysine and L-arginine on primary osteoblast cultures from normal and osteopenic rats." Biomed Pharmacother. 2001 May;55(4):213-20.
  • Shaheen E Lakhan, Karen F Vieira. "Nutritional and herbal supplements for anxiety and anxiety-related disorders: systematic review." Nutrition Journal. October 2010. 9:42doi:10.1186/1475-2891-9-42. 7.
  • Singh BB, Udani J, Vinjamury SP, Der-Martirosian C, Gandhi S, Khorsan R, Nanjegowda D, Singh V. "Safety and effectiveness of an L-lysine, zinc, and herbal-based product on the treatment of facial and circumoral herpes." Altern Med Rev. 2005 Jun;10(2):123-7.
  • Smriga M, Ando T, Akutsu M, Furukawa Y, Miwa K, Morinaga Y. "Oral treatment with L-lysine and L-arginine reduces anxiety and basal cortisol levels in healthy humans." Biomed Res. 2007 Apr;28(2):85-90.