8 Questions veterinarians should ask before treating poisoned patients

Every second counts when treating poisoned patients. For most substances, there's only a narrow time frame in which decontamination can be effectively and safely performed. Here are 8 questions to consider before inducing vomiting on the poisoned pet.

1. When did the ingestion occur? In most cases, vomiting can safely be induced within an hour of ingestion. If it’s been several hours since the ingestion, most likely the toxicant has already moved out of the stomach and vomiting will be of limited or no benefit to the pet.^1,2 Certain toxins can delay gastric emptying (e.g., salicylates, opioids, anticholinergics) or remain in the stomach for a prolonged period of time (e.g., chocolate, large wads of xylitol gum, grapes or raisins, large ingestions of tablets or capsules that form a bezoar). In these specific situations, vomiting induction can be performed in asymptomatic patients up to four hours after ingestion.¹
2. Does the patient have any symptoms? Induction of vomiting in a pet that’s already vomiting or symptomatic is not warranted. Pets that are sedate or have an altered state of consciousness may be at increased risk of aspiration pneumonia secondary to vomiting induction. In many situations, gastric lavage1 performed under intubation—to protect the airway—may be required. Pets that present in an excited state can have clinical signs further exacerbated during vomiting induction, thus worsening their condition. Again, as the patient is already symptomatic, they have likely already absorbed most of the drug or toxin.
3. Is there a species or breed concern with induction of vomiting? Brachycephalic breeds of dogs (e.g., bulldogs, Pekingese, Shih-Tzus) may present a higher risk of aspiration pneumonia and are candidates for sedation, airway protection, and gastric lavage. Species that can be safely induced to vomit include most dogs, cat, ferrets, and potbelly pigs. Rabbits, rodents (e.g., chinchillas, rats, gerbils), ruminants (e.g., sheep, cattle, llamas, goats), horses, and birds can’t safely be induced to vomit or may be anatomically unable to vomit.³
4. Is there an underlying medical concern or condition? Megaesophagus, laryngeal paralysis, or a previous history of aspiration pneumonia are a few examples of conditions that may increase the risk for aspiration pneumonia when inducing vomiting.¹
5. Is the toxicant caustic or corrosive? Any substance that’s corrosive and capable of causing burns and caustic injury can further injure the stomach, esophagus, and mouth when inducing vomiting. Examples are batteries, undiluted drain cleaners, toilet bowl cleaners, lime-removal products, and concentrated pool products. With poisoning from this type of ingestion, vomiting induction is contraindicated.
6. Is the toxicant a hydrocarbon or petroleum distillate? These low-viscosity liquids are easy to aspirate into the lungs, and vomiting induction is not recommended. Some frequently encountered hydrocarbons and petroleum distillates include gasoline, kerosene, tiki torch fuels, motor oils, and furniture polish oils.
7. Is the toxicant zinc, calcium, or aluminum phosphide? These are active ingredients in many commercially available mole and gopher baits. Ingestion of these phosphide rodenticides can result in the formation of a toxic phosphine gas in the stomach. This gas can harm owners and clinic staff when the pet vomits, potentially causing headache, nausea, and bronchial-type reactions (like asthma). Induction of vomiting should occur outdoors or in a well-ventilated area after administration of an antacid (e.g., aluminum hydroxide, milk of magnesia).
8. How fast will the patient develop clinical signs with this toxicant? Large ingestion of human medications can result in rapid occurrence of life-threatening clinical signs. It’s important to determine if and when pharmaceutical ingestion will result in sudden changes in blood pressure, heart rate, central nervous system mentation, or neurologic abnormalities (e.g., seizures, hyperagitation, tremors). Since many medications (e.g., selective-serotonin reuptake inhibitors, quick-release drugs, sublingual pills) can cause clinical signs right away, pet owners should not be told to induce vomiting at home without appropriately consulting a veterinarian or Pet Poison Helpline.

1. Lee JA. Decontamination of the Poisoned Patient. In: Osweiler G, Hovda L, Brutlag A, Lee JA, ed. Blackwell’s Five-Minute Veterinary Consult Clinical Companion: Small Animal Toxicology, 1st Ed. Iowa City: Wiley-Blackwell, 2010, pp. 5-19.
2. Peterson ME. Toxicological Decontamination. In: Peterson ME, Talcott PA, ed. Small Animal Toxicology, 2nd Ed. St. Louis: Elsevier Saunders, 2006, pp. 127-141.
3. Bihun C, Bauck L. Basic Anatomy, Physiology, Husbandry, and Clinical Techniques. In: Quesenberry K, Carpenter JW, eds. Ferrets, Rabbits, and Rodents, 2nd Ed. St Louis: Elsevier Saunders, 2004, pp 289-290.

Veterinarians: Learn more about treating pet poison victims

Pet Poison Helpline has many critical resources on pet poisonings, some of which we've worked with Wedgewood Pharmacy to compile for you in one eBook. Download the eBook from the Resources for Veterinarians section of WedgewoodPetRx. Additionally, you can attend webinars for CE credit. Register for the next online presentation at PetPoisonHelpline.com. Pet Poison Helpline will be guest blogging here for a few weeks to share with you this important information on treating pet poisonings.

Justine Lee, DVM, DACVECC Associate Director of Veterinary Services Pet Poison Helpline

About Justine Lee, DVM:
Dr. Justine Lee is a board-certified emergency critical care veterinary specialist, and is currently the Associate Director of Veterinary Services for Pet Poison Helpline. For the previous five years, she was on faculty as an Assistant Clinical Professor at the University of Minnesota College of Veterinary Medicine.

Dr. Lee graduated from Virginia Tech with a BS in Animal Sciences, and then obtained her veterinary degree at Cornell University. She pursued her internship at Angell Memorial Animal Hospital, which is affiliated with the Massachusetts Society for the Prevention of Cruelty to Animals (MSPCA). In addition, she has also completed an emergency fellowship and residency at the University of Pennsylvania. Currently, she is 1 of approximately 450 board-certified veterinary specialists world wide in emergency and critical care, and is a Diplomate of the American College of Veterinary Emergency and Critical Care (DACVECC).

Dr. Lee has been published in numerous veterinary journals, including the Journal of American Veterinary Medical Association, the Journal of Veterinary Emergency Critical Care, and the Journal of Veterinary Internal Medicine. She is also the author of two humorous pet reference books entitled “It’s a Dog’s Life... but It’s Your Carpet” and “It’s a Cat’s World... You Just Live In It.” Dr. Lee lectures throughout the world on emergency and critical care, and recently was honored with the North American Veterinary Conference Small Animal Speaker of the Year award for 2011.

Connect with Wedgewood Pharmacy: