Rat Bait (Bromethalin Rodenticide) Toxicosis in Dogs

Key Takeaways

Bromethalin toxicosis in dogs is caused by ingestion of a toxic dose of bromethalin-based rodent poison. 

• Ingestion of bromethalin is often fatal and there is no antidote to the poison

• If caught quickly, it’s possible to remove enough of the poison by inducing vomiting or consuming activated charcoal to avoid a lethal dose

• There is no safe way to induce vomiting in a dog at home. Any dog suspected of ingesting poison needs emergency veterinary care

• Symptoms of bromethalin poisoning include muscle tremors, paralysis, seizures, and involuntary eye movements

• There is no practical or timely way to test for bromethalin toxicosis and treatment is symptomatic and supportive

• Prognosis is poor once symptoms start

• The most effective prevention of death or neurologic impairment from bromethalin toxicosis is to prevent access to bromethalin in the first place

A Closer Look: What is Bromethalin Poisoning in Dogs?

Bromethalin-based rodenticides are often used as pest control. Since dogs tend to be indiscriminate eaters and rodenticides are usually designed to seem like food, it is easy for dogs to ingest different types of bait during their outdoor activities. Consumption of a toxic dose of bromethalin rat poison is life threatening. It is vital to determine the amount consumed, if witnessed, to determine the level of danger the pet is in. If symptoms begin to show, the prognosis is very poor and there is no antidote to the poison. A pet parent should not attempt to induce emesis without first consulting a vet. There is no safe way to induce vomiting without medical guidance.

The first symptom is ideally the discovery of the dog eating the bromethalin, which is commonly produced as pellets or green blocks. Once this is observed, any information about the volume consumed or any packaging information for the poison is essential. All of this information will be invaluable to the vet to assist the pet.

Risk Factors

Bromethalin toxicosis develops in two different presentations in dogs, depending on the size of the dosage ingested relative to body weight. The convulsant form usually occurs when a large dose is ingested and symptoms develop within 4 hours of exposure. The paralytic form usually occurs after smaller exposures and symptoms develop 1 - 4 days after ingestion has occurred. If symptoms have begun to present, the prognosis is very poor. The paralytic form of poisoning is sometimes successfully treated, especially if caught early enough and treated aggressively.

Possible Causes

Bromethalin toxicosis is caused by ingestion of a toxic dose of bromethalin mouse/rat poison.

Main Symptoms

Symptoms of toxicosis are broken into two categories, convulsant and paralytic. 

Symptoms of convulsant form include:

• Hyperexcitability • Muscle tremors • Seizures • Death

Symptoms of paralytic form include:

• Vomiting • Loss of appetite • Involuntary eye movements • Muscle tremors • Paralysis

Testing and Diagnosis

When ingestion is not witnessed, a pet presenting with typical symptoms undergoes routine diagnostic testing such as physical examination, bloodwork, and urinalysis. Specific diagnostic tests to identify bromethalin in the kidneys, fat, liver, or brain can be done, but are only practical for post-mortem use.

When a pet comes in for treatment immediately after ingestion, the goal is to remove as much of the poison as possible and prevent its absorption by using the following strategies:

• Inducing vomiting • Gastric lavage • Activated charcoal

There is no antidote, so treatment is symptomatic and supportive, and may include: 

• Muscle relaxants • Sedatives • Anti-seizure medications • IV fluids

Once a dog develops symptoms, the odds of survival are very small.

Steps to Recovery

The best chance for survival for a dog who eats a toxic dose of bromethalin is rapid decontamination to effectively reduce the ingested dose to a safe level. Once symptoms appear, the prognosis becomes poor as there is no antidote to the toxin. Dogs who survive bromethalin toxicosis may have permanent neurological damage.

Prevention

Bromethalin poisoning is not contagious. It is prevented by eliminating the possibility of exposure. This is achieved by using alternate pest control methods and keeping outdoor dogs leashed in public places where unknown use of rodenticide may be at play.

Is Bromethalin Poisoning Common in Dogs?

Bromethalin poisoning is only reported in areas where this type of pest control is common. Overall, rodenticide toxicosis of all types are commonly reported in dogs each year.

Typical Treatment

Decontamination:

• Emesis induction• Activated charcoal

Symptomatic therapy:

• Muscle relaxers • Sedatives • Anticonvulsants