From the manufacturer's website:
Don’t let cold sores stop you in your tracks. Used at the first sign of a tingle, Abreva® cream acts fast to tackle a cold sore at its source. Abreva® cold sore cream can heal a cold sore in as few as 2½ days when used at the first sign of an outbreak.
Abreva® cream shortens the time it takes to get rid of a cold sore. Its unique formulation uses the active ingredient Docosanol to penetrate deep into the heart of your cold sore.
Abreva® cold sore cream contains 10 percent docosanol, which works by penetrating deep into the skin and preventing the cold sore virus’ entry into healthy cells, stopping viral replication. It provides a barrier to protect healthy skin cells and helps to heal the cold sore quickly. Docosanol also helps to shorten the duration of cold sore symptoms, such as tingling, pain, burning and itching.
*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.