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
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