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Mouth, Teeth or Throat Symptoms
Cold Sores

A cluster of painful tiny (1-3 mm) small bumps or blisters on the outer lip. Typically, there are 3-5 blisters within a ½ inch (10 mm) area. The small blisters often rupture and form 1 big sore (i.e., cold sore).
Present only on one side of the mouth (i.e. doesn't cross the midline)
Also referred to as Fever Blisters

General Information

Cause: Cold sores are recurrent painful blisters on the outer lip caused by the Herpes simplex virus (usually Type I).
Primary Herpes Simplex: Approximately 80% of the adult population has had herpes simplex at some point in their lives. The very first episode (primary herpes simplex) of infection can present as sores on the inside of the mouth (with fever and feeling sick). More commonly, people have no symptoms at all during the first episode.
Recurrent Herpes Simplex Labialis (Cold Sores): After the first episode of Herpes, the Herpes virus stays hidden in a facial sensory nerve. It can be reactivated by sun exposure, fever, friction, trauma, menstrual periods, stress or physical exhaustion. Such recurrences occur in 20% of the adult population. Typically, the symptoms are confined to the lip and there is no fever. The medical term for these recurring cold sores of the lip is Herpes Simplex Labialis. Another term that people use for this condition is Fever Blisters. This is a self-limiting illness that resolves without any treatment in 7-10 days.

Are there any over-the-counter treatments for cold sores?

Docosanol cream (Abreva) seems to reduce severity, pain and duration of cold sores (Sacks 2001). Docosanol is FDA approved. Ask your physician's opinion.

What can your physician prescribe for colds sores?

Topical (cream) prescription treatment with Pencylcovir 1%: Use of this cream four times daily has been shown to reduce the severity, pain and duration of cold sores in adults (Spruance 1997). It is more expensive than docosanol.
Oral (pills) prescription treatment - Available oral anti-viral medications include acyclovir (Zovirax), famcyclovir (Famvir), and valacyclovir (Valtrex). However, the research is not conclusive and such treatment is not standard practice (Emmert 2000). You will need to discuss this with your physician. There may be some modest benefit obtained from using these medications; these medications may shorten symptom duration by 1 day and reduce symptoms.