If Abreva is applied when a cold sore first appears, healing can take less than three days, according to the Abreva website. The median healing time is about four days. GlaxoSmithKline, the manufacturer of Abreva, recommends that people use the medication for no longer than 10 days.
Abreva is the brand name for docosanol, a topical medication that minimizes symptoms of cold sores and speeds up the healing time, explains WebMD. Abreva blocks the herpes simplex virus, which causes cold sores, from invading healthy skin cells and proliferating. Abreva does not cure herpes, nor does it prevent an infected individual from passing the virus to another person. It also does not prevent the recurrence of cold sores.