Why a sink basin makes this worse for a small cat
When drain cleaner spills into a sink, it often pools in concentrated amounts rather than diluting across a large surface. Your 3 kg cat licking from this puddle likely ingested more of the chemical than if she'd touched a freshly cleaned surface. Alkaline drain cleaners rapidly break down proteins in tissues, which is why mouth and throat damage appears quickly.
The first signs you'll see involve her mouth—excessive drooling, reluctance to swallow, or pawing at her face. These indicate chemical burns starting to form. Unlike some toxins that take hours to show effects, drain cleaner damage begins within minutes. Even if she seems okay now, internal injuries may be developing where you can't see them.
What to do in the next 30 minutes
Do not attempt home remedies like milk or water—these won't neutralize the alkali and may worsen nausea. The priority is preventing further throat damage by keeping her from swallowing more of the chemical. If she's drooling, place a towel under her chin to catch saliva rather than letting her lick it back.
Check her gums and tongue for redness, swelling, or white patches—these signal tissue damage. Any vomiting, especially with blood or coffee-ground material, means the stomach lining is affected. Keep her calm and contained in a carrier while you contact the vet, as stress can accelerate toxin absorption.
Why weight matters with alkaline burns
A 3 kg body has less tissue to absorb and dilute the chemical compared to a larger animal. The same few licks that might cause mild irritation in a 10 kg dog can create deep ulcers in a cat's esophagus. Small pets also dehydrate faster from drooling and vomiting, complicating recovery.
Watch her breathing closely—swelling in the throat can partially obstruct airways. Rapid shallow breaths or neck stretching suggest narrowing passages. Even if she seems stable now, delayed swelling from tissue damage can appear hours later as inflamed areas continue to break down.
The critical 48-hour window
Alkali burns keep penetrating deeper for up to two days after exposure. Your vet will monitor for perforations in the esophagus or stomach, which are life-threatening. They may withhold food initially to rest the damaged tissues, using IV fluids instead.
Long-term complications include strictures—scar tissue that narrows the esophagus—which may require repeated dilation procedures. Cats with throat burns often need soft foods for weeks and frequent follow-ups to catch delayed effects. Early treatment improves outcomes, so don't wait for severe symptoms to appear.
The step-by-step response, from the first minute to the vet visit, is in our Drain Cleaner Toxicity in Dogs and Cats emergency guide.