Why one candy demands two responses
The exposed cat needs immediate bloodwork — xylitol's hypoglycemic effects aren't always proportional to dose. Some cats crash rapidly on small amounts due to individual sensitivity. Your unexposed cat still needs observation; cats sometimes share food secretly or groom toxins off each other.
Separate them now. Stress can mask symptoms in the affected tabby, while the 'well' cat may seek comfort near her companion. Use different rooms, not just opposite sides of a carrier — xylitol poisoning can cause disorientation and aggression.
How sugar-free differs from regular candy
Hard candies often contain xylitol in the outer coating, which dissolves quickly in saliva. Even if the tabby didn't swallow the whole piece, she ingested concentrated sweetener from the surface. Regular candy would mainly risk diabetes or diarrhea — sugar-free risks organ failure.
Check the ingredient list for alternate names: birch sugar, E967, or 'natural sweetener.' Many brands mix xylitol with erythritol or stevia, but assume it's present unless proven otherwise. Even 'tooth-friendly' labels often indicate xylitol.
Why time matters more than quantity
Xylitol's peak danger window is 30 minutes to 12 hours post-ingestion. Your tabby's 4 kg size buys minimal time — larger cats may buffer the toxin slightly longer. Don't wait for the 10-hour mark; early intervention prevents liver damage that becomes irreversible.
If you can't reach your vet within 20 minutes, prepare to go to emergency. Have her carrier ready and note any behavior changes en route. Time the onset of any symptoms — this helps vets calculate toxicity progression. Bring the candy wrapper or a photo of its ingredients.
The hidden risk for the 'safe' cat
Monitor the unaffected cat for 24 hours — she may have licked residue you didn't witness. Cats investigate dropped items together, and sugar-free candies leave less sticky evidence than gummies would. Check her gums for stickiness and watch for unusual thirst.
Even minus xylitol, some sugar-free candies contain sorbitol or mannitol, which can cause diarrhea in sensitive cats. If her stool softens or she vomits, it doesn't necessarily mean poisoning — but report it to rule out secondary exposure. Separate litter boxes help track who's affected.
The full verdict, portion guidance and serving notes are collected on the Candy food facts page.