Common toxicoses in small animal practice: a guide for the veterinary nurse

Toxicology cases in veterinary medicine are not as commonly seen in primary practice as infectious disease or trauma. However, veterinary nurses or technicians should have a working knowledge of the common toxicants in order to know what pertinent questions to ask when taking a patient's history, anticipate what clinical signs they can expect to observe in their patient during nursing care, and help provide medically correct answers to common questions owners may ask about the poison. The focus of this article is on some of the toxicants commonly identified with small animal patients.

A toxicant is any poison, while a toxin is a poison that comes from a biological origin (e.g. tetanus toxin and toad toxin). Most toxicants produce an acute onset of clinical signs, although there are some exceptions to the rule. One example are anticoagulant rodenticides and ethylene glycol (antifreeze), which cause toxicity after being metabolised to a more toxic ingredient or produce a secondary physiological effect that manifests as toxic signs. Therefore, if a patient was fine in the morning and now is ill in the afternoon, toxicants and trauma (physical or biological, such as a ruptured splenic tumor) should be at the top of the differential list for causes (Gupta, 2007). Even relatively rapidly appearing infectious diseases usually have prodromal clinical signs before the onset of significant disease noticed by the owner. During admission of the patient, this chronology of clinical signs (clinically normal in the morning, ill by afternoon) should prompt the veterinary nurse or technician to ask questions about the animal's environment, opportunities to access potentially toxic agents (e.g. access to a garage, unsupervised outside, etc), human medications in the household to which the pet may have access, and any other questions that can help the veterinarian identify the potential for toxicity.