What IV fluids accomplished at the vet
The fluids helped flush ibuprofen metabolites from your cat's system and maintained blood flow to her kidneys during the critical first 12 hours. They also corrected any early electrolyte imbalances that could have caused seizures or heart irregularities. Your vet likely chose a specific fluid type based on her blood work results.
Despite this intervention, kidney tubules may still be recovering from inflammation. The IV didn't 'cure' the exposure—it bought time for her body to process the toxin. Ongoing hydration remains crucial, which is why you're being told to encourage water intake now.
Monitoring a 4 kg cat's delicate balance
Small cats dehydrate faster when unwell. Weigh her daily using a kitchen scale—a 100g weight loss equals significant fluid depletion at her size. Check her skin elasticity at the shoulders twice daily; if the tent doesn't snap back immediately, she needs vet attention.
Her litter habits tell more than her appetite right now. Normal urine output for her weight is about half a cup daily—measure clumps with a disposable measuring cup. Hard, dry stools or overly watery urine both warrant a callback to your vet.
The hidden recovery period ahead
Kidney damage from NSAIDs sometimes appears 3-5 days post-exposure, after initial blood tests normalize. Your vet may schedule a follow-up creatinine test later this week even if she seems fine. Don't mistake increased sleepiness for normal convalescence—cats hide pain until they're critically ill.
Her stomach lining remains vulnerable for up to a week. Transition back to regular food gradually, starting with wet food diluted with water. Any treats or new foods could irritate healing ulcers. Keep her on bland diet until cleared by your vet.
When to disrupt her rest for the vet
Watch for subtle neurological signs like staring at walls, excessive vocalization, or misjudging jumps—these indicate possible metabolic disturbances. A cat her size can develop dangerous blood sugar or potassium levels quickly when kidneys are stressed.
If she isolates herself from you persistently or shows sudden disinterest in favorite sleeping spots, these are red flags in feline recovery. Trust these behavioral cues over obvious physical symptoms—cats compensate until they can't. Nighttime declines are common, so don't wait until morning if something feels off.
The step-by-step response, from the first minute to the vet visit, is in our Topical Ibuprofen Poisoning in Dogs and Cats emergency guide.