Preliminary investigation of the administration of biperiden to reduce relapses in individuals with cocaine/crack user disorder: A randomized controlled clinical trial.

Background: Several studies have demonstrated that ACh modulates the dopaminergic circuit in the nucleus accumbens, and its blockade appears to be associated with the inhibition of the reinforced effect or the increase in dopamine caused by cocaine use. The objective of this study was to evaluate the effect of biperiden (a muscarinic receptor antagonist with a relatively higher affinity for the M1 receptor) on crack/cocaine use relapse compared to a control group that received placebo.

Methods: This study is a double-blind, randomized, placebo-controlled clinical trial.