They’re painful, unsightly and they always seem to come at the wrong time! Cold sores are caused by a form of the herpes simplex virus, or HSV-1, and appear as clusters of blisters often at the corners of the mouth or on the lips. The first infection is usually the worst; however, recurrences are common and can be triggered by stress, sun exposure, colds and menstruation. The blisters are contagious and may weep clear fluid before forming a scab. One acquired, HSV-1 is within the body for life.

Since the herpes virus cannot be eradicated, research has focused on preventing recurrences or shortening their duration. There are a few natural remedies that show promise in research.

Lysine: This amino acid is perhaps the most commonly used natural cold sore remedy — and rightly so. Lysine inhibits viral replication and studies show it can both prevent outbreaks, reduce symptom severity and shorten the duration. In one study, people who took lysine at the first sign of an outbreak had a “rapid resolution” in all cases. Lysine and lysine-based remedies are available in capsules, liquid, creams and lip applicators. Food sources of lysine include fish, chicken, yogurt, cottage cheese and wheat germ.

Vitamin C: Researchers report that vitamin C supplements and topical creams can lessen severity and shorten the duration of cold sores. For one of these studies, people with herpes infections took either a placebo or 200 mg of vitamin C plus 200 mg of flavonoids, three to five times per day. The researchers found that, compared with the placebo, vitamin C and flavonoids reduced the duration of symptoms by 57%.

Cranberry: Researchers at the Kaohsiung Medical University in Taiwan recently isolated a compound from cranberry and found that it significantly suppressed HSV-2 (genital herpes) infection. Since both types of the virus tend to respond to the same treatments, it’s likely that the cranberry compound may inhibit HSV-1 as well. The researchers say the cranberry reduced the effects of the infection by “preventing viral attachment and penetration, and disturbed the late stage of infection.”

Lemon Balm (Melissa): Widely used for the treatment of cold sores in Europe, lemon balm contains several anti-herpes components. Many studies have indicated dramatically reduced healing times and few or no recurrences. These studies used lemon balm cream, which is common in Europe but as yet hard to find in North America. However, some herbalists suggest that using lemon balm tea and applying it directly to the sores with cotton balls may be just as effective.

Sources: The Green Pharmacy by J Duke, St Martin’s:1997; Encyclopedia of Natural Medicine (2nd Ed) by M Murray and J Pizzorno, Prima:1998; Chemistry & Industry, Oct 15, 2004; healthnotes.com