According to the Centers for Disease Control and Prevention, 45 million people in the United States are infected with herpes. According to Harrison's Principles of Internal Medicine, systemic agents are the most effective treatments for herpes. However, for people who are unable to tolerate systemic agents, three topical herpes treatments have been also been approved by the Food and Drug Administration.
Acyclovir
Topical acyclovir (Zovirax cream, Zovirax ointment) is usually applied five times daily for four days, according to Medline Plus, a patient information website jointly maintained by the National Library of Medicine and the National Institutes of Health. It is most effective against oral herpes (cold sores or fever blisters) when used at the beginning of an outbreak. It is substantially less effective than oral therapy for first outbreaks of both oral and genital herpes. It has shown no benefit for genital lesions in recurrent outbreaks.
Penciclovir
Penciclovir (Denivir cream) is the active metabolite in the systemic drug famciclovir. According to Dr. Sharon Safrin, associate professor of medicine at the University of California, San Francisco, topical penciclovir is effective for the treatment of recurrent oral herpes. When applied within one hour of symptom onset and continued every two hours (during waking hours) for four days, penciclovir reduced the median time until cold sore healing by 17 hours compared to a placebo.
Docosanol
Docosanol (Abreva) is a saturated 22-carbon aliphatic (fat-containing) alcohol that prevents the herpes virus from entering the cells by disrupting the interaction between the membrane of a person's cells and the herpes virus envelope. Docosanol is a common ingredient in cosmetics and personal care products and, unlike the other drugs listed here, it is available without a prescription. As reported by Safrin, when applied five times a day, beginning within 12 hours of the first sign of an outbreak, docosanol reduced mean healing time of recurrent cold sores by 18 hours compared to a placebo.
References
- Herpes Simplex Viruses (Chapter); L. Corey; In: Harrison's Principles of Internal Medicine, 17th edition; A.S. Fauci, E. Braunwald, D.L. Kasper, S.L. Hauser, D.L. Longer, J.L. Jameson, and J. Loscalzo (Eds.); 2008
- Antiviral Agents (Chapter); S. Safrin; In: Basic & Clinical Pharmacology, 11th edition.; B.G. Katzung (Ed.); 2009
- Medline Plus: Topical Acyclovir
