Can early administration of pregabalin reduce the incidence of postherpetic neuralgia?

Conflict of interest: The authors declare that they have no conflicts of interest. Postherpetic neuralgia (PHN) is a common complication of herpes zoster (HZ), and is very difficult to treat. The issue of neuropathic pain should be considered even during the acute phase of HZ, because nerve injury begins before the appearance of the vesicular rash. This aim of this study was to investigate whether early administration of pregabalin could decrease the incidence of PHN. The study was approved by the ethics committee of Hiroshima Red Cross Hospital, Hiroshima, Japan. Informed consent was not needed, as this was a retrospective study from clinical dermatological records. Patients received treatment as usual. From the clinical dermatology records in our hospital, gathered between June 2010 and June 2012, 82 patients with HZ were identified. Pregabalin had been given to 57 of the 82 patients (69.5%), and was continued until the pain ceased. The 57 patients were divided into two groups based on how soon after HZ onset the drug was initially administered: within 7 days (group A, n = 26) or after 7 days (group B, n = 31). Variables studied were the incidence of PHN (defined as pain that continued for ≥ 3 months1), risk factors for PHN,2 dose of and adverse reactions to pregabalin, and use of other drugs. Data were analysed using unpaired t‐test or Mann–Whitney U‐test. P < 0.05 was considered significant.