By Ann Hohenhaus, DVM
In my last post I wrote about rodenticides and the dangers they pose if ingested by our animal companions. This post will describe the clinical signs and treatment of dogs with rodenticide intoxication, including both anticoagulant and vitamin D poisons.
The photograph shows a hemorrhage in the retina from rodenticide poisoning.
Ingestion of this type of rat poison by dogs typically causes internal hemorrhage, anemia, and, in the worst cases, death. If your dog has ingested this type of poison, you might notice a bloody nose, blood in the stool or urine, and a general lack of energy from anemia due to blood loss. Many dog owners do not realize rat poison has been placed by their landlord or an exterminator until an emergency room veterinarian suspects rodenticide intoxication. A blood test showing abnormal blood clotting can confirm the diagnosis.
Anticoagulant rodenticide intoxication can be successfully treated. The antidote is vitamin K, but not the type of vitamin K available in a health food store; a prescription is required. Severely ill dogs will require hospitalization, blood transfusions, and close monitoring in an intensive care unit. The good news is, most will recover.
Vitamin D analogues
Minor elevations in blood calcium caused by ingestion of vitamin D analogue rat poisons will cause your pet to increase its drinking and urination. If the exposure to vitamin D analogue rat poison is prolonged or the amount ingested large, kidney damage, seizures, and death can occur.
For veterinarians, making a diagnosis of vitamin D rodenticide intoxication can be challenging. An increase in drinking and urination is not specific for vitamin D rodenticide intoxication and is a common finding in several disorders, including diabetes, kidney failure and pyometra.
Routine bloodwork can readily identify elevated calcium levels, but like an increase in drinking and urination, elevation of calcium levels is nonspecific and occurs in several disorders, including kidney failure, lymphoma, and an overactive parathyroid gland. A dog with elevated calcium levels often needs an extensive medical evaluation to determine if rodenticide intoxication is causing the elevation in calcium levels.
Treatment of vitamin D rodenticide intoxication can be equally as challenging and require administration of several different treatments to bring the calcium down. Hospitalization is frequently required for administration of intravenous fluids and diuretics. The hormone calcitonin has also been used to lower dangerously high calcium levels and steroids may also be used to increase calcium excretion in the urine.
An ounce of prevention is worth a pound of cure, and in the case of rodenticides, cautious use could save your pet’s life. The Environmental Protection Agency has a very useful consumer website on rodenticides and their safe use in homes with pets. It may be worth your pet’s life to check it out.