Rodenticide Toxicity in Dogs

mt. carmel animal hospital rodenticide toxicity in dogs

Regarding rodenticide toxicity in dogs, identifying the active ingredient is crucial because this will determine the poisoning risk and the necessary treatment.

Although various rodenticides might appear alike and have similar names, they contain very different poison types. Regarding rodenticide toxicity in dogs, identifying the active ingredient is crucial because this will determine the poisoning risk and the necessary treatment. Mount Carmel Animal Hospital wants to share the four prevalent active rodenticide ingredients, how they work, their symptoms, treatment, and dangers of ingestion.

Types of Rodenticides


Anticoagulant rodenticides were once the most popular type of poison on the market. While they are still found, they are becoming less common due to regulatory changes. This type of poison works exactly how it sounds. By inhibiting the enzyme Vitamin K1 and therefore, clotting factors, anticoagulant rodenticides disrupt the body’s ability to clot its own blood. This leads to uncontrolled bleeding.

When cats or dogs ingest this active ingredient, signs of poisoning are visible 3 to 5 days after consumption. However, the onset of clinical signs might be sooner if your pet has been chronically exposed to the product. Blood loss initially occurs internally, and the common signs include weakness, coughing, difficulty breathing, pale gums, and exercise intolerance. Less common symptoms include diarrhea, vomiting, bloody urine, nosebleed, swollen joints, and gum bleeding.

Moreover, vitamin K1 is the antidote for anticoagulant rodenticides. Due to the level of inhibition of vitamin K1, over-the-counter multivitamins with K1, menadione (vitamin K3), or high vitamin K foods are not enough to counteract the effects of the toxin. If rodenticide toxicity in dogs occurs, they will need to be treated with prescription-strength oral Vitamin K1 for up to 10 days (short-acting) or 30 days (long-acting). In severe cases, Vitamin K1 can be given intravenously. Some pets also require a blood or plasma transfusion depending on to replace blood cells and the clotting factors. In all cases, your dog’s clotting factors will need to be monitored for several days after ingestion.

Dogs are quite sensitive and require veterinary intervention if they have ingested this type of rodenticide. With some baits (brodifacoum), it only takes a minor amount to cause rodenticide toxicity in dogs, while others have a more comprehensive safety range (bromadiolone). Additionally, the pet’s age and health might determine whether or not the amount consumed will be poisonous. Animals with gastrointestinal disease or underlying liver disease, despite their age, are more at risk.

Cholecalciferol (Vitamin D3)

Cholecalciferol is one of the most dangerous rodenticides for dogs and cats. Due to changes in EPA regulations, this type of poison is becoming more and more common than the anticoagulants we used to see. This poison causes hyperphosphatemia and hypercalcemia. As a result, severe acute kidney failure and other tissue damage can occur. The common signs of poisoning include increased drinking and urinating, weakness, decreased appetite, lethargy, and halitosis (bad breath). By 2 to 3 days after ingestion, significant damage has occurred to the pet’s kidneys. Without immediate intervention, this damage is often permanent. This type of poisoning can be challenging to treat since hospitalization, regular and repeated lab monitoring, and expensive therapy is often necessary for a positive outcome. Aggressive IV fluid therapy is required for the first days after ingestion.

Frequent blood work monitoring is often necessary throughout the 2 to 6 weeks after ingestion. Fluid therapy is continued as needed, either through IV fluids or via subcutaneous fluid administration. This includes phosphorus, calcium, and renal values. Additionally, cholecalciferol has a very narrow margin of safety; even minor ingestions of this poison can result in clinical signs or death. Ingestions must be treated right away to prevent kidney failure.


Bromethalin has been a popular rodenticide for several decades as a response to rodents that were showing resistance to the anticoagulant types of poison. This neurotoxic rodenticide provokes cerebral edema in your pet. Bromethalin functions by detaching oxidative phosphorylation in the brain, which can lead to cerebral edema. Cats are more sensitive to this poison than dogs are, but the safety margin is very small in all animals and any ingestion is a medical emergency. Common signs of poisoning include tremors, incoordination, paralysis, and eventually death.

The more significant the ingestion, the more severe and rapidly occurring the clinical signs may be. Medical monitoring for at least 24 hours after ingestion is often necessary. Since Bromethalin has long-lasting effects, in-hospital care for several days may be required. The treatment might include several doses of activated charcoal. Activated charcoal works to prevent the body from absorbing the toxins. Medications to reduce brain swelling and IV fluids will also be administered.

Zinc & Aluminum Phosphides

Even though these gas-producing poisons are commonly found in gopher or mole baits, they might appear in rat and mouse baits. Other concerns are lung irritation and possible toxicity when you or the veterinary staff inhale fumes from your pet’s vomit. Phosphine gas is released once it’s in your pet’s stomach. Food in the stomach will boost the amount of gas produced and increase the poison’s toxicity. Therefore, feeding pets after ingestion of this poison is never recommended. The phosphine gas produced causes clinical signs, including vomiting, stomach bloating, seizures, collapse, shock, and liver damage.

There is no antidote for this toxin, and immediate treatment is necessary. Antacids after ingestion, can help to decrease gas production. It is critical to decontaminate the stomach by inducing vomiting or performing gastric lavage. Because your pet’s vomit can cause toxicity in you, it is best to leave emesis to the professionals. Veterinary staff will have the proper equipment and protocols to keep everyone safe.

As with the other rodenticides, even small doses can lead to clinical signs, and any ingestion should be treated as a medical emergency. Contact Mount Carmel Animal Hospital immediately to bring your pet in for care. If your dog happens to vomit in the car on your way here, all windows should be opened to help prevent inhalation of the toxic phosphine gas. Do not attempt to clean the vomit yourself.


Mount Carmel Animal Hospital has been serving the Northern Baltimore/Southern York community for over 30 years and is proud to be an independently operated, small animal practice committed to excellence in veterinary medicine and client service. From grooming to wellness services, along with Canine Life Skills Training Courses, and surgical procedures, we have the expertise that will best serve the needs of you and your pet. Contact us at 410-343-0200 and follow us on Facebook!

This entry was posted on Friday, January 27th, 2023 at 8:55 am. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.