Recent studies of valacyclovir (the L-valine ester of acyclovir, which has 3 to 5 times greater bioavailability) offer the most promise for effective self-initiated treatment of recurrent herpes labialis. In a report of 2 well-designed, multicenter RCTs, valacyclovir at the FDA-approved dosage of 2 g twice daily for 1 day at the onset of symptoms (before visible signs of a cold sore) significantly decreased the mean duration of the lesion and time to lesion healing. In the first study (n=603), episode duration was decreased by 1.1 days (5.0 days vs 6.1 days for placebo; 95% CI, –1.6 to –0.6) and in the second study (n=605) by 1.0 day (5.3 vs 6.3 days for placebo; 95% CI, –1.0 to –0.5). In the first study, the time to lesion healing was decreased by 1.3 days (4.8 vs 6.1 days for placebo; 95% CI, –1.9 to –0.7) and in the second study by 1.2 days (5.1 vs. 6.4 days; 95% CI, –1.8 to –0.7). There also was a trend towards preventing the development of lesions, but this was not statistically significant.4
Recommendations from others
The BMJ Clinical Evidence Guideline reiterates that no trials compare early vs late treatment, so no firm conclusions about the efficacy of delayed treatment can be drawn.5 UpToDate reports that HSV 1 studies take into account that acyclovir acts only during active viral replication, which largely precedes symptoms, and thus suggest that it has little effect if begun after the appearance of lesions.6
CLINICAL COMMENTARY
For late presenters, review local care and hygiene; for all patients, review management of recurrences
Owen McCormack, DO
Baylor College of Medicine, Houston, TX
Patients seek treatment for herpes labialis due to bothersome physical symptoms and psychosocial implications. Many patients can identify prodromal symptoms such as localized itching, burning, irritation, or pain. Diagnosis of the initial episode is frequently delayed as patients are evaluated after the time period when studies have shown the most benefit from antivirals. For the late presenters, I review local care and hygiene, and for all patients I review management of recurrences.
Patient-initiated treatment is effective for those who can recognize the earliest signs and symptoms and start treatment immediately with either a topical or systemic antiviral. Both formulations decrease the lesion time to healing and pain if started at the first onset of symptoms.
Cost is an important consideration when selecting a particular formulation. Approximate price for the regimens presented here are $12 for 5 days of oral acyclovir, $27 for 1 day of oral valacyclovir, and $37 for a 2-g tube of acyclovir cream, which can be used for more than 1 episode.7 Other factors to consider are pill burden, duration of treatment, patient preference, and lifestyle. Patients can keep a refill or medicine on-hand to manage recurrences with the advice to begin immediately with onset of signs or symptoms.