How two weeks of nibbles add up
Each tiny dose your senior cat ingested over two weeks has accumulated in her liver, overwhelming her vitamin K recycling system. Unlike a single large exposure, this chronic poisoning means her body hasn't had time to recover between doses. At 3 kg, her small liver struggles to process the toxin efficiently, allowing it to build up to dangerous levels even from minor daily amounts.
The poison's effects are now self-sustaining — as her clotting factors deplete, minor internal bleeds release more stored toxin back into her bloodstream. This creates a vicious cycle where each small hemorrhage makes the next one more likely. Her age complicates matters further, as older cats often have reduced liver and kidney function even before the poisoning.
Silent damage you can't see
By now, microscopic bleeding may be occurring in her brain, lungs, or digestive tract without obvious external signs. Senior cats often mask symptoms until they're severe — what looks like "just slowing down" could actually be blood loss anemia. Check her gums for paleness and press gently to see if the pink color takes more than 2 seconds to return after you release.
Watch for small changes in litter box habits — straining to defecate (from intestinal bleeding) or urine that looks more concentrated than usual (as her kidneys try to conserve fluid lost internally). Blood may appear as dark flecks in vomit or stool rather than the bright red many owners expect.
Why standard treatments need adjusting
For chronic exposure like this, your vet will likely recommend higher vitamin K doses and longer treatment than for a single incident — possibly 6-8 weeks instead of the usual 4. Blood tests will monitor not just clotting times but also liver enzymes and red blood cell counts to assess existing damage.
Your cat may need subcutaneous fluids to support circulation if she's anemic, but blood transfusions are risky in chronic cases because the stored toxin can attack the new blood cells too. The vet might suggest ultrasound to check for internal bleeding that isn't showing on bloodwork yet, especially in her abdomen or around her heart.
The recovery timeline isn't linear
Even with treatment, improvement comes in stages — first stabilizing active bleeding, then rebuilding clotting factors, and finally clearing the toxin from her system. Setbacks are common, especially in the first 10 days when stored poison keeps releasing from her liver. Don't be alarmed if her energy fluctuates; this reflects her body's ongoing repair work.
Long-term, your senior cat may need liver support supplements beyond the vitamin K therapy. Keep her strictly indoors during recovery — a minor fall or scrape that would normally heal quickly could become dangerous while her clotting system remains fragile. Recheck any bait stations in your home; older models may have leaks or cracks allowing chronic low-level exposure.
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.