An epidemiology and biostatistics student (what a mouthful!) answered the question of –how effective is therapy for preventing recurrence of cold sores due to herpes labialis?

Cold sores are commonly caused by herpes simplex virus type 1.  More than 90% of us have been exposed to this.  1/4 of us with HSV1 experience periodic viral reactivation, usually in the form of a cold sore on our lip.

The 10 studies showed that acyclovir and valcyclovir (two commonly prescribed antivirals) are more effective than placebo (sugar pills) in stopping recurrences of cold sores.  Systemic therapy (pills) were more effective than topical (cream).  All forms of medication were well tolerated by patients.

So, if you are plagued by cold sores, talk to your doctor about therapy.