The Goal To determine the characteristics of depression as side effect of tetrabenazine (TBZ) treatment for hyperactive movement disorders including Huntington’s.
The Method The authors reviewed medical charts of 518 tetrabenazine treated patients (162 with Huntington’s and the rest with medically related movement disorders) and split them into two groups; those who had prior history of depression, and those who did not. The authors then checked for onset of depression, or the worsening of depression within these two groups after starting tetrabenazine.
The Findings Of those patients with no history of depression, 11.4% developed it on tetrabenazine. Of those with history of depression 18.4% experienced worsening. But - of great importance - only 3% of patients, equally distributed between the two groups chose to discontinue tetrabenazine due to depression. Though specifics were not reported in this review, this low rate of discontinuation suggests that careful dosage adjustment and/or treatment with antidepressants controlled these symptoms.
Why is it Important? This first report to focus on characteristics of tetrabenazine-induced depression is very important because Huntington’s has a high incidence of depression and suicide. The results are reassuring because, in long term follow-up, only 3% chose to stop the drug because of depression. This gives compelling support to the argument that tetrabenazine-induced depression is treatable, and that most patients find this drug beneficial.
Also important are those who report improvement in depression after taking the drug. Though the authors did not provide actual numbers of such patients, they conclude the review by saying “Many patients with prior depression note marked improvement not only in their hyperkinetic movement disorder but also in their depression, possibly as a result of improvement in their quality of life.”
Author comments We applaud doctors J. Jankovic and C. Kenney (who had no funding from Prestwick Pharmaceuticals) for this review and for their decades-long support for the treatment of chorea and other hyperkinetic movement disorders.
Kenney C, Hunter C, Mejia N, Jankovic J. Is history of depression a contraindication to treatment with tetrabenazine? Clin Neuropharmacol. 2006 Sep-Oct;29(5):259-64. PubMed abstract