A double-blind study comparing idazoxan and bupropion in bipolar depressed patients

There is a small body of evidence indicating that idazoxan, a potent and selective alpha-2 antagonist, may be effective in treating bipolar depressive disorder. The purpose of this prospective controlled study is to compare idazoxan to bupropion, an antidepressant which has been suggested to have some advantages over other antidepressants in treating bipolar depressed patients.

Bipolar I depressed patients were randomly assigned in this 6-week double-blind out-patient study to receive either idazoxan, titrated to 240 mg/day and placebo bupropion, or bupropion, titrated to 450 mg/day and placebo idazoxan. These doses were achieved after 2 weeks. Depression severity was assessed with the Hamilton Depression Rating Scale and possible psychosis with the Brief Psychiatric Rating Scale. Side effects, heart rate, weight, and orthostatic blood pressure were also monitored.

Fourteen patients completed this study (seven in each group). Both idazoxan and bupropion demonstrated significant improvement over time with reductions in Hamilton scores of 50%.

Limitations of this study include lack of a placebo group and small sample size.

In light of our preliminary findings suggesting the usefulness of idazoxan in bipolar depression, larger more rigorous studies are indicated.