Hepatopathy in 4 dogs treated with amiodarone

Amiodarone is a class III antiarrhythmic drug used in dogs with dilated car diomyopathy and ventricular tachyarrhythmias. Hepatopathy is one of the mor e commonly reported adverse effects of amiodarone use in people. We describ e 4 dogs that developed hepatopathy associated with amiodarone administrati on: 2 dogs also developed neutropenia. Three dogs hud clinical signs of ano rexia and lethargy; 1 did not show signs until impaired liver function had developed. Clinical signs or biochemical abnormalities developed 1.5-8 mont hs after amiodarone treatment was started. Clinical signs resolved within 2 weeks of discontinuing amiodarone, but biochemical abnormalities did not r esolve for 6-8 weeks. The delay between onset of liver disease and overt cl inical signs suggests that serial evaluation of liver enzyme activities fol lowing amiodarone use in dogs is important.