Complexity of oxytocin׳s effects in a chronic cocaine dependent population.

Behavioral and neuroplastic changes occurring in the development of addiction parallel those that occur in social bonding. This has led to speculation that drugs of abuse co-opt systems that subserve social attachment to shift attachment to drugs of abuse. Oxytocin, a neuropeptide that is important in social bonding, has been shown in rodents to decrease psychostimulant self-administration, locomotor activity, and conditioned place preference, it is unclear what role it may play in human drug addiction. In this double-blind, placebo-controlled crossover study, 23 cocaine-dependent inpatients in court-ordered treatment completed 4 task sessions measuring desire to use cocaine, cue-induced craving, monetary reward decisions and social cognition. Before each session, subjects administered 24 IU of intranasal oxytocin or placebo. Oxytocin increased desire to use cocaine and cue-induced excitability with no effect on cue-induced desire to use. Oxytocin also removed the effect of state anger on several measures of cue reactivity. Response to monetary reward increased under oxytocin and measures of social cognition worsened. The significant increase in the desire for drug and monetary reward as well as the significant decrease in measures of social cognition was small but warrant further study of the effect of oxytocin׳s effect in cocaine dependent subjects. The effect of oxytocin to modulate the relationship between state anger and cue reactivity should be explored further for potential therapeutic use of oxytocin in cocaine dependent patients. These findings are discussed in light of the human and rodent oxytocin literature.