Objective. To assess the effect of Banisteriopsis caapi and Psychotria viridis ‘binomio ayahuasca’ ingestion in rat hippocampus. Design. Experimental, descriptive, analytical, and cross-sectional study. Institution. Research Institute of Pharmaceutical Sciences and Natural Resources, Faculty of Pharmacy and Biochemistry, Universidad Nacional Mayor de San Marcos, Lima, Peru. Biological material. Rats. Interventions. Orogastric administration of ‘binomio ayahuasca’ in adult Rattus norvegicus albinus Holtzman strain. Seven groups of five animals with an average weight of 240 ± 30 g were administered: (GI) placebo, (GII) 2.5 mL of diazepam (GIII) 0.7 mL of Banisteriopsis caapi solution, (GIV) 0,7 mL of Psychotria viridis solution. Groups GV, GVI and GVII received 0.7 mL, 3.5 mL and 7.0 mL of binomio ayahuasca solution, respectively. Main outcome measures. Macroscopically: reflex mov...