Effects of trazodone on behavioral and physiological signs of stress in dogs during veterinary visits: a randomized double-blind placebo-controlled crossover clinical trial

Abstract

Abstract OBJECTIVE To determine whether a single dose of trazodone administered to dogs before a veterinary visit reduced their behavioral and physiologic signs of stress and owners’ stress during veterinary visits. SAMPLE 20 dogs and their owners. PROCEDURES In this randomized double-blinded placebo-controlled crossover clinical trial, dogs with a history of anxiety during veterinary visits were scheduled for 2 veterinary visits 1 week apart and randomly assigned to receive a single oral dose of either trazodone (9 to 12 mg/kg) or a placebo 90 minutes before transport to the veterinary clinic for alternate visits between September 21 and November 3, 2019. For each visit, we collected and assessed owner-completed surveys of dog stress score (DSS) and owner stress score; various investigator-reported scores, including from video-recorded behavior analyses; and patient-related physiologic data. RESULTS Dogs treated with trazodone versus placebo had lower mean DSSs, assessed by owners for physical examination and assessed by video analysis for time spent in the examination room; lower mean SD of normal-to-normal intervals, root mean square of successive heartbeat interval difference, and respiratory rate; and higher mean heart rate. No meaningful differences were observed in other behavioral or physiologic outcomes, including serum cortisol concentrations. CLINICAL RELEVANCE A single dose of trazodone before transport reduced signs of stress during veterinary visits for dogs in the present study and may be useful as an anti-anxiety medication for similarly affected dogs, potentially resulting in higher-quality clinical examinations and improved patient welfare.