Assess the situation
Have the bait package in hand. The active ingredient and its percent are printed on the label.
Emergency vet or poison control: which do I call?
Because there is no antidote, getting the bait out of the stomach early is the main treatment. Merck Veterinary Manual recommends inducing vomiting if the ingestion was within 4 hours and the pet has no signs, followed by multiple doses of activated charcoal. Decontamination should be done by a vet, who also watches sodium levels while charcoal is given.
Go straight to an emergency vet if…
- Your pet ate any bromethalin bait, especially in the last 4 hours
- Your pet is wobbly, weak in the back legs, trembling, overly excited, depressed, or having a seizure
- Your pet is a cat, a puppy or kitten, or very small
- You cannot tell how much bait is missing
Call poison control first if…
- You are not sure the poison is bromethalin and need help reading the label
- You found the bait days ago and your pet seems normal
- You want a case number and a treatment plan to hand to your vet
How bromethalin poisoning develops
Bromethalin is absorbed quickly and converted in the body into a compound that disrupts energy production in brain and nerve cells. Fluid builds up in the brain and spinal cord, which causes the signs below. The timing and type of signs depend on the dose.
Convulsant syndrome (larger doses in dogs)
- Hyperexcitability, muscle tremors
- Seizures, high body temperature
- Can be fatal
Paralytic syndrome (smaller doses, and cats)
- Wobbly walk, back leg weakness
- Depression, odd behavior
- Paralysis
Delayed and lasting effects
- Signs can first appear days after eating the bait
- Recovery from nerve damage can take weeks
- Some damage may be permanent
Published data behind these estimates
These figures are from Merck Veterinary Manual and ASPCA Animal Poison Control Center publications. LD50 means the dose that killed half the animals in a study. Severe poisoning has been reported in pets at doses below the LD50, so there is no safe amount.
| Dose or fact | Documented effect |
|---|---|
| Dogs: about 0.24 mg/kg | Toxic dose, taken as one tenth of the lowest reported LD50 (Merck) |
| Dogs: 2.38 to 5.6 mg/kg | Reported LD50 range (Merck) |
| Dogs: about 3.54 mg/kg | Average LD50; doses at or above this may cause seizures within 4 to 36 hours (Merck) |
| Cats: about 0.04 mg/kg | Toxic dose, one tenth of the lowest reported LD50 (Merck) |
| Cats: 0.4 to 0.71 mg/kg | Reported LD50 range (Merck). Cats are the most sensitive pets. |
| 0.01% bait | Contains 0.1 mg of bromethalin per gram of bait. Most baits are 0.01% to 0.025% (Merck). |
Every result on this calculator is labeled Emergency, because bromethalin has no antidote and a narrow safety margin. The message changes with the estimated dose: for dogs, at or above 0.24 mg/kg (toxic dose), at or above 2.38 mg/kg (lowest reported LD50), and at or above 3.54 mg/kg (average LD50, seizure risk). For cats, at or above 0.04 mg/kg (toxic dose) and at or above 0.4 mg/kg (lowest reported LD50). Below the toxic dose the result still says to call now, because individual pets vary and amounts eaten are usually uncertain.