Suspected hepatotoxicity secondary to trazodone therapy in a dog

To describe a case of suspected hepatotoxicity in a dog secondary to administration of trazodone.

A 6-year-old, neutered, mixed breed dog was evaluated for a progressive increased liver enzyme activity over a 6-week period. The patient originally presented for raisin toxicosis, and hence, was having serial blood work monitoring performed. Trazodone was initially started at that time due to severe separation anxiety while hospitalized (consistently 5 out of 7 days of the week, for a 6-week duration). Due to continued increased liver enzyme activity, extensive workup was performed which included abdominal ultrasound, leptospirosis titers, bile acids, and liver biopsies. Histopathologic findings were consistent with acute hepatotoxicity. In the absence of other toxicants and the close proximity to drug administration, a drug-induced hepatopathy secondary to trazodone was presumed. Following discontinuation of trazodone therapy, the hepatopathy completely resolved and the patient fully recovered.

While acute hepatotoxicity has been reported in human medicine secondary to the administration of trazodone, this is the first reported case of suspected hepatotoxicity in a dog secondary to trazodone therapy. Veterinary professionals should be aware of the rare potential adverse effect that may be seen in canine patients secondary to trazodone therapy. Appropriate clinicopathologic monitoring should occur in patients on chronic trazodone therapy.