The Role of Calcium Channel Blockers in the Treatment of Psychiatric Disorders

Summary Calcium channel blockers (CCBs) inhibit the influx of calcium ions into excitable cells through long-acting (L-) channels. Four classes of CCBs have been synthesised, all with greater activity in hyperactive than in normal cells in diverse systems. Although more generally used for the treatment of cardiovascular disorders, CCBs have been shown to be effective in a number of psychiatric disorders. Verapamil, the most widely studied of the CCBs, has been found to be superior to placebo and equivalent to lithium in the treatment of mania. However, most trials have been small and no multi centre studies have been performed. CCBs may prevent antidepressant-induced mania and reduce the frequency of rapid cycling in bipolar disorder, and they may have applications in panic disorder. The antidepressant properties of CCBs remain to be clearly demonstrated. CCBs generally are well tolerated, but still experimental, alternatives to lithium and anticonvulsants in the treatment of bipolar mood disorders.