Comparison of the effects of adrafinil, propentofylline, and nicergoline on behavior in aged dogs

OBJECTIVE: To compare the efficacy of adrafinil, propentofylline, and nicergoline for enhancing behavior of aged dogs. ANIMALS: 36 Beagles between 9 and 16 years old. PROCEDURE: Dogs were randomly assigned to receive adrafinil (20 mg/kg of body weight, PO, q 24 h; n = 12), propentofylline (5 mg/kg, PO, q 12 h; 12), or nicergoline (0.5 mg/kg, PO, q 24 h; 12) for 33 days. Baseline behaviors in an open field and in kennels (home cage) were recorded before treatment. After treatment, behaviors in the open field were recorded 2 hours after drug administration on days 2, 15, and 28, and 10 hours after administration on days 7, 20, and 33. Behaviors in the home cage were recorded 2 and 7 hours after drug administration on days 4, 17, and 30. RESULTS: Treatment with adrafinil resulted in a significant increase in locomotion in each of the open-field tests and an increase in locomotion in the home cage. This latter increase was smaller and more variable than that in the open field. Locomotion was not affected by treatment with propentofylline or nicergoline. In the open field, sniffing decreased over time in all 3 groups, but the largest decline was observed in the propentofylline group. CONCLUSIONS AND CLINICAL RELEVANCE: Treatment with adrafinil may improve the quality of life of aged dogs by increasing exploratory behavior and alertness.