A controlled trial of amlodipine for cocaine dependence: a negative report

Preclinical models of cocaine dependence have shown favorable reductions in cocaine use using dihydropyridine calcium channel antagonists. This is one of the first reports testing the efficacy of the long-acting calcium channel antagonist, amlodipine, for the treatment of cocaine dependence. This was a 12-week, double-blind, randomized, placebo-controlled, parallel patient group trial of amlodipine vs. placebo for the treatment of cocaine dependence. One hundred and sixteen subjects participated in a 12-week medication trial in which 60 subjects received medication and 56 received placebo. Subjects in both groups received up to 12 standard manual-driven cognitive behavioral therapy sessions. Overall, drop-out rate for both groups was high, with only about 20% of subjects completing all 12 weeks of treatment. Both groups showed comparable levels of medication compliance and therapy attendance. In the end, amlodipine was no more effective than placebo in reducing craving or measured levels of cocaine use.