How does Denavir work (mechanism of action)? After applying Denavir to a cold sore, the active ingredient, penciclovir, penetrates into the infected cells to block the multiplying of the virus that causes the cold sore.
Possible Side Effects
Denavir was generally well tolerated in all clinical trials -- the most frequently reported adverse events with Denavir and placebo in the pivotal trials, respectively, were headache (5.3% vs 5.8%) and application site reaction (1.3% vs 1.8%). In the most recent trial the adverse events were no different.