Ayahuasca, a hallucinogenic brew, prevents the development of ethanol-induced behavioral sensitization in mice and reverses established sensitization. A single dose (30–500 mg/kg) blocked the initiation of behavioral sensitization without affecting spontaneous movement. Higher doses (300 and 500 mg/kg) selectively reduced both acute and sensitized responses to ethanol. Eight consecutive days of ayahuasca (100 or 300 mg/kg) after sensitization was established blocked its expression upon a subsequent ethanol challenge. The results suggest ayahuasca may inhibit early addiction-related behaviors and reverse long-term drug effects when administered in the ethanol-associated environment.
Ayahuasca, a hallucinogenic beverage used in traditional Amazonian rituals, blocked the reinstatement of methylphenidate-induced conditioned place preference in mice, indicating reduced drug-seeking behavior. Both ayahuasca (100 mg/kg, orally) and methylphenidate (10 mg/kg, i.p.) separately induced conditioned place preference. However, methylphenidate altered Fos expression in several limbic brain regions associated with drug abuse, while ayahuasca had limited effects on Fos expression. Treatment with ayahuasca after conditioning with methylphenidate prevented reinstatement of the conditioned place preference and generally blocked the changes in Fos expression induced by methylphenidate conditioning or reexposure. These findings suggest ayahuasca restored normal brain function in areas linked to long-term drug wanting or seeking.