Gabapentin for Postherpetic Neuralgia

To the Editor: Published clinical trial reports often fail to adequately document safety findings.¹ In this respect, Dr Rowbotham and colleagues² should be commended for providing detailed safety data in their study on the use of gabapentin for the treatment of postherpetic neuralgia.

However, some of the adverse event (AE) reporting appears to have been filtered. Unlike the analysis comparing the incidence rates between groups for the most frequently reported AEs, the reporting of AEs that were minor or severe and those that led to withdrawal from the trial were restricted to events deemed related to the study medication by the investigator. One of the primary reasons for using a randomized, double-blind study design is to eliminate, or at least reduce, bias in the reporting of AEs. Restricting analyses to only those events deemed related to the study medication by the investigators has the potential to defeat one of the aims of this research method. Hence, it would be of value to see all of the AE data from the study by Rowbotham et al analyzed, irrespective of investigator-assigned causality.