Disulfiram treatment for cocaine dependence in methadone-maintained opioid addicts

Aims. Cocaine use by patients on methadone maintenance treatment is a widespread problem and is associated with a poorer prognosis. Recent studies have evaluated disulfiram as a treatment for individuals with comorbid alcohol and cocaine abuse. We evaluated the efficacy of disulfiram for cocaine dependence, both with and without co-morbid alcohol abuse, in a group of methadone-maintained opioid addicts. Design, Randomized double-blind, placebo-controlled trial. Setting. Urban methadone maintenance clinic. Participants. Sixty-seven cocaine-dependent, methadone-maintained, opioid-dependent subjects (52% female; 51% Caucasian). Intervention. Study medication, either disulfiram or placebo, was placed directly in the methadone to ensure compliance for 12 weeks. Measurements. Primary outcome measures included weekly assessments of the frequency and quantity of drug and alcohol use, weekly urine toxicology screens and breathalyzer readings. Findings. Disulfiram treated subjects decreased the quantity and frequency of cocaine we significantly more than those treated with placebo. Alcohol use was minimal for all subjects regardless of the medication. Conclusions. Disulfiram may be an effective pharmacotherapy for cocaine abuse among methadone-maintained opioid addicts, even in those individuals without co-morbid alcohol abuse. Disulfiram inhibits dopamine beta-hydroxylase resulting in an excess of dopamine and decreased synthesis of norepinephrine. Since cocaine is a potent catecholamine re-uptake inhibitor, disulfiram may blunt cocaine craving or alter the "high", resulting in a decreased desire to use cocaine.