Gabapentin Treatment of Mood Disorders: A Preliminary Study

Objective: To determine if gabapentin is effective either as adjunctivetreatment or as monotherapy for major affective disorders in a naturalistic setting.

Method: All charts of patients meeting DSM-IV criteria for bipolardisorder or unipolar major depressive disorder treated with gabapentin in a privatepsychiatric practice were reviewed and clinical response was assessed retrospectivelyusing the Clinical Global Impressions scale for Improvement (CGI-I).

Results: Gabapentin was moderately to markedly effective in 30% (15/50)of patients, with statistically nonsignificant differences between patients with bipolardisorder type I, bipolar disorder type II and NOS, and unipolar major depressive disorder.70% reported side effects, mainly sedation, with 16% of the total sample discontinuingtreatment due to adverse events.

Conclusion: Gabapentin appears to be somewhat effective as add-ontreatment in a subgroup of patients with mood disorders in a naturalistic setting.Prospective, controlled studies are required to clarify these pilot data.