Apomorphine hydrochloride: a clinical review with retrospective analysis of use in 1126 dogs treated in emergency practice

Apomorphine is a non-selective dopamine agonist commonly used in veterinary medicine for the emergency management of toxicoses in dogs, through the induction of emesis. This review evaluates the currently reported effectiveness, adverse effects and recommendations of apomorphine as an emetic and considers alternatives. This is complemented by a retrospective study of 1126 dogs treated with apomorphine in emergency practice, to determine the efficacy of apomorphine in a clinical setting, and to provide identification of population characteristics, indications and outcomes of treated patients. The literature recognises apomorphine as a successful and consistent emetic for the retrieval of ingested harmful substances, with generally mild and self-limiting adverse effects. The retrospective study found that the most common reasons for presentation of the treated population were chocolate (26.8%), rodenticide (26.5%), foreign material (20.7%), and medication ingestion (11.6%). In this study, the two most influential factors on emetic and clinical outcome were the type of intoxicant and length of ingestion-to-presentation time. Breed size was an important determinant for the type of substance ingested, with variations noted between small, medium and large breed dogs. The most commonly estimated time from ingestion to presentation was 1–2 hours, with the substance, or parts thereof, successfully identified in the vomitus of 68.9% of cases. Apomorphine remains a valuable veterinary therapeutic for use in small animal emergency and critical care, providing a high rate of successful induction of emesis.