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Cincinnati, OH
A 22-year-old male asked:

I understand that valtrex (valacyclovir) is most effective at the first sign of a breakout, but is taking it after a cold sore erupts effective at all? thanks!

2 doctor answers2 doctors weighed in
Dr. Stephen Scholand
Infectious Disease 25 years experience
Herpes cold sore: Cold sores on the lips are painful and can be distressing to us. The best thing to do is prevent them from coming out by avoiding the STRESS that allows them to occur. If this fails, Valtrex (valacyclovir) is most useful when the tingling is there BEFORE the red blister. Once the infection has the upper hand, it's harder to catch up. save the Valtrex (valacyclovir) for next time- no sense in training ur virus 2B resistant 2it
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Michael Fisher
Dermatology 34 years experience
Valtrex (valacyclovir): This medication works best when started at the first sign of an outbreak, as directed by your doctor. It may not work as well if you delay treatment.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Aug 24, 2015

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