Why the color and shape of the bait matter right now
Green block baits often contain brodifacoum or bromadiolone, anticoagulants that cause delayed but severe internal bleeding. The waxy texture makes it easy for cats to ingest more than they spit out, as it sticks to their teeth and gums. Your cat may seem fine for 2-5 days before showing weakness or pale gums—but by then, clotting factors are already depleted.
Time is critical because vitamin K1 therapy must start before symptoms appear. Unlike other toxins, the danger here isn’t immediate vomiting or seizures, but silent damage. Grab the packaging to confirm whether this is an anticoagulant (most common), cholecalciferol, or neurotoxic type—each requires entirely different emergency protocols.
How much your cat swallowed versus how much matters less than you think
Even a pea-sized amount of some rodenticides can be fatal to cats over days. The bait’s concentration varies wildly—some blocks contain 0.005% active ingredient, others 0.05%. Don’t rely on estimating ‘just a bite’; assume the worst until you have the product name.
Cats are especially sensitive to anticoagulants due to their small size and unique metabolism. A 4 kg cat eating half a gram of brodifacoum needs treatment, even if dogs might tolerate that dose. The vet will calculate risks based on the package’s mg/kg listing, not your guess of consumption.
The deceptive calm before bleeding begins
In the first 24 hours, your cat may act completely normal—no drooling, no lethargy, no visible distress. This is when owners often mistakenly assume the danger has passed. But anticoagulants work by depleting vitamin K-dependent clotting factors, which takes time.
Watch for subtle changes: slightly labored breathing could mean lung hemorrhage, reluctance to jump might indicate joint bleeding. Pale gums or a single speck of blood in saliva warrant immediate ICU care. By the time you see nosebleeds or bloody stools, transfusions may be needed.
Why you can’t wait to see symptoms
Anticoagulant rodenticides are insidious—they damage silently, and treatment becomes harder once clotting is impaired. Vitamin K1 injections must begin within hours to outpace the toxin’s effects, not after symptoms show. Your vet may also administer plasma if bleeding has already started.
Bring the bait package even if torn or incomplete. Modern rodenticides often combine multiple toxins (e.g., anticoagulant + bromethalin), requiring layered treatments. If the packaging is lost, your cat will need broader monitoring—blood tests every 48 hours for at least two weeks.
The step-by-step response, from the first minute to the vet visit, is in our Rat Poison (Rodenticide) Poisoning emergency guide.