Fighting Drug Dependence by Blocking Cannabinoid Type 1 Receptors

Drug dependence is a chronic relapsing brain disorder characterized by neurobiological changes that lead to a compulsion to take a drug with loss of control over drug intake. Abused drugs (cannabinoids, opioids, ethanol, nicotine and psychostimulants) by interacting with various neural pathways in brain induces pleasant state and responsible for relapses. All abused drugs have common property of elevating dopamine levels in nucleus accumbens. Currently the treatments available for drug dependence are not satisfactory and the most successful smoking cure clinic by using a combination of treatments achieve a success rate of less than 30%. Cannabinoid receptors are coexpressed in the brain reward circuitry and recent preclinical and human studies have suggested that ligands blocking the CB1 receptors offer a novel approach for patients suffering from drug dependence that may be efficacious across different classes of abused drugs. This review examines the role and current status of cannabinoid CB1 receptor antagonist in drug dependence.