3 doctors weighed in:
How fast does acyclovir work on cold sores?
3 doctors weighed in

2 doctors agree
In brief: Depends...
...On the time lag between breakout and start of treatment.
After 3 days may not work at all.

In brief: Depends...
...On the time lag between breakout and start of treatment.
After 3 days may not work at all.
Dr. Anatoly Belilovsky
Dr. Anatoly Belilovsky
Thank
Get help from a real doctor now
Dr. Shontae Buffington
Board Certified, Pediatrics
13 years in practice
833K people helped
Continue
107,000 doctors available
Read more answers from doctors