Gabapentin and Tinnitus Relief

his editorial and commentary was prompted by the publication of Picirillo et al.’s “Relief of idiopathic subjective tinnitus: Is gabapentin effective?” [1], which concluded that gabapentin was no more effective than a placebo in relieving tinnitus. The goal of this editorial and commentary is constructive: to provide to tinnitus patients and professionals involved with tinnitus diagnosis and treatment (1) a protocol for patient selection in considering an innovative drug application (i.e., gabapentin [GP]) for attempting tinnitus relief; (2) an assessment of the biases in the study that—though scientifically and statistically valid—have led the authors to a conclusion that is not clinically relevant; (3) an understanding of the rationale underlying our recommendation of a combined therapy including GP ; and (4) a basic understanding of the activity of GP and the concepts of inhibition and neuroprotection. In general, our recommendation and experience with GP has been positive for achieving tinnitus relief over the long term in a particular cohort of tinnitus patients. Specifically, selected tinnitus patients are those who have accurately diagnosed clinical, predominantly central-type severe, disabling subjective idiopathic tinnitus (SIT). GP has not been recommended as a single therapy for tinnitus patients, but as part of a combined therapy attempting tinnitus relief after identification and treatment of factors known to influence the clinical course of the SIT [2]. GP, a drug designed originally as a supplement for seizure control, was considered for those SIT patients in whom objective evidence of abnormal electrical and metabolic brain activity was identified. Initially, nuclear medicine imaging with single-photon emission computed tomography (SPECT) of the brain provided objective metabolic evidence [3]. Since 2000, quantitative electroencephalography (QEEG) has provided electrophysiological evidence [4]. Both tools have been used not only for diagnosis but as a monitor for objectively identifying the efficacy of GP and combined treatment. In our experience, long-term tinnitus relief with GP supplemented by clonazepam (Klonopin) was reported initially at the 2001 American Academy of Otolaryngology– Head and Neck Surgery meeting and published in 2002 in the International Tinnitus Journal [2]. It is unfortunate that the design of the study conducted by Picirillo et al. [1] did not reflect state-ofthe-art tinnitus diagnosis and treatment at this time. On learning of this effort to establish the efficacy of GP for tinnitus relief, our team supported it and corresponded with the primary author to share our experience. Specifically, a highlight of our correspondence was to alert the primary investigator to the following: “In general, protocols of treatment, which did not differentiate between different clinical types of tinnitus, will provide conflicting results” [5]. The authors elected to disregard that alert. Consequently, as predicted, the results and conclusions in that report are biased. The results reflect methods of patient selection and tinnitus evaluation that are not state of the art, thereby confusing tinnitus patients and professionals attempting tinnitus diagnosis and treatment in matters of GP efficacy for tinnitus relief.