A pilot open-label study of oral acetazolamide for sodium valproate-associated weight gain in bipolar affective disorder

Background: Bipolar affective disorder (BD) is a chronic recurrent disorder having a definite link with metabolic abnormalities, including obesity, dyslipidemia, and insulin resistance. Drugs approved for the treatment of BD include sodium valproate but have weight gain as a metabolic side effect. An increase in weight is one of the common reasons for discontinuation of mood stabilizers. There is a need for a weight loss agent which will not increase mood symptoms in bipolar disorder. This study looks at the effect of acetazolamide on weight when combined with sodium valproate in patients diagnosed with BD in remission. Materials and Methods: This pilot quasi-experimental open-label 8-week follow-up study was conducted in a tertiary care teaching hospital following clearance from the institutional ethics committee. Thirteen outpatients with BD who reported weight gain on sodium valproate monotherapy received oral acetazolamide 500 mg/day. A specialized pro forma was used to record demographic and physical data with side effects. Results: The mean baseline weight was 70.15 ± 8.75 kg and the mean baseline body mass index was 25.09 ± 2.61. The mean sodium valproate dose of the study population was 692 mg/day. Ten of 11 individuals who completed the study showed some reduction in weight and nine showed a slight decrease in abdominal girths. Conclusion: There was a nonsignificant decrease in weight and abdominal circumferences at the end of 8 weeks, however, since it is a small pilot study, we need more evidence.