Limited evidence finds modest benefit in favour of antivirals for the prevention of cold sores

The Dental Elf, 2012

Limited evidence finds modest benefit in favour of antivirals for the prevention of cold sores » The Dental Elf
The usual cause is the herpes simplex virus type 1 (HSV-1) although HSV-2 is been increasingly implicated.
20-30% of those infected experience outbreaks of  small blisters or sores on or around the mouth with frequencies ranges from monthly to annually.
Triggers include sunlight, trauma, fever, stress, and dental treatment.  They are self limiting but can cause significant discomfort.
The aim of this review was to the effectiveness of antiviral agents in the prevention of Recurrent herpes labialis (RHL).
An extensive literature search was conducted that included Cochrane Central Register of Controlled Trials, Medline, and Embase  databases and a wide range of other resources.
No language restrictions were applied, and all relevant non–English-language papers were translated.
Only randomised controlled trials were included, quality assessment and data synthesis followed methods  described in the .
10 studies matched the inclusion criteria, only 1 paper had a low risk of bias, 5 an  unclear risk and  4 papers a high risk of bias.
A significant difference in favour of antiviral agents when all 10 trials were pooled (RR 0.70, 95% CI 0.55-0.89).
Oral acyclovir (800-1,600 mg daily) and valacyclovir (500 mg daily for 4 months) were shown to be effective in the prevention of RHL when taken prior to the appearance of any symptoms or exposure to triggers.