How a rice-sized crumb becomes deadly
That tiny crumb contains enough poison to kill multiple mice — and your 3 kg cat has about the same body mass as 10-15 mice combined. Anticoagulant baits are designed to be lethal in single feedings, so even this minuscule amount is concentrated danger. The poison's effects multiply over time as it disrupts vitamin K cycles, meaning the small dose keeps working against her system for weeks.
Cats are especially vulnerable because they metabolize toxins more slowly than dogs. Her liver will struggle to break down the compound, allowing it to accumulate faster. The first signs you might notice — weakness, pale gums, or slight lameness — actually represent advanced internal bleeding that started days earlier.
Why you can't rely on visible symptoms
Unlike some poisons that cause immediate vomiting or diarrhea, anticoagulants work silently. Your cat could be bleeding into her joints, chest cavity, or brain without any external evidence. Small cats decompensate faster than larger animals when blood loss occurs — a few teaspoons of internal bleeding can be life-threatening at her size.
Watch for subtle changes like increased sleeping (not just normal cat napping), reluctance to jump, or breathing slightly faster than usual. These suggest her body is struggling with oxygen delivery due to blood loss. Unlike dogs, cats rarely show obvious bruising until they're critically ill.
The misleading safety of bait stations
You might think the bait station protected your cat, but crumbs often scatter when rodents nibble at the blocks. Cats ingest these while grooming their paws after walking near the station. Even secondhand poisoning is possible if she ate a rodent that had consumed the bait, though that typically takes more time to cause symptoms.
The station's design doesn't account for a 3 kg animal's curiosity and dexterity — some cats learn to manipulate them. If this happened in your home, assume there are more crumbs hidden in corners or under appliances. Until you've cat-proofed the area completely, confine her to a safe room with no access to potential poison sources.
Emergency steps for tiny patients
Time matters more than quantity with anticoagulants — even this small amount requires immediate vitamin K intervention. Your vet will likely give an injection followed by oral supplements for 3-6 weeks. Blood tests to monitor clotting times usually start 48 hours after ingestion when the poison's effects become measurable.
For a cat this small, the vet may recommend hospitalization for observation, as fluid therapy helps support circulation if bleeding starts. Don't be misled by her current normal behavior; the toxin works on a cellular level long before clinical signs appear. Recovery depends on starting treatment before symptoms develop, not after.
The step-by-step response, from the first minute to the vet visit, is in our Anticoagulant Rodenticide Toxicity in Dogs and Cats emergency guide.