Why mould matters more than sugar for a 5 kg cat
The granulated sugar itself isn’t the issue—it’s the mould that grew on it during that week on the counter. Cats lack sweet taste receptors, so they don’t seek out sugar, but they might lick it accidentally while exploring. For a cat of this size, even a few licks of mouldy sugar could introduce enough spores to irritate her stomach lining, though severe poisoning is unlikely.
Mould exposure often causes signs within 4–12 hours: excessive lip-licking, drooling, or turning away from food. If she ate a substantial amount (like a teaspoon’s worth), you might see vomiting or diarrhoea as her body tries to expel the irritants. Since cats hide discomfort well, note any unusual lethargy or refusal to eat her next meal.
What to watch for in the next 24 hours
Focus on two things: her hydration and litter-box habits. Mould-induced stomach upset can lead to subtle dehydration—check if her gums feel tacky or if the skin at her scruff stays tented when gently pinched. Sugar alone won’t cause this, but vomiting or diarrhoea from mould might. Her stools may be looser or smell more pungent than usual.
If she’s still playful, drinking water, and using the litter box normally, she’s likely handling it. But if she vomits more than once, has watery diarrhoea, or stops interacting with you, those are signs her system needs help. Cats dehydrate quickly, and a 5 kg cat can’t afford to lose much fluid.
When to skip monitoring and call the vet
Two scenarios warrant an immediate vet visit: if she’s already showing neurological signs (stumbling, tremors, or dilated pupils—rare with mould but possible with certain fungi) or if she has pre-existing conditions like inflammatory bowel disease. Older cats or those with kidney issues may struggle more with even mild dehydration from vomiting.
For most healthy cats, mouldy sugar causes a day of mild discomfort. But if she’s diabetic, even this small sugar intake could briefly affect her blood glucose. While one lick likely won’t spike levels dangerously, combine it with mould exposure, and it’s worth updating your vet.
How to prevent future counter surfing
Cats are drawn to textures and smells, not sweetness. The grainy feel of sugar might attract paws, while mould adds a fermented odour. Store sugar in sealed containers, and wipe counters with vinegar (cats hate the smell) to deter exploration. If she’s a chronic counter-jumper, provide elevated shelves or cat grass to redirect her curiosity.
After this incident, watch for new aversions—some cats associate the upset stomach with the counter itself and avoid it. If she starts drooling or pawing at her mouth later, she might have a mild oral irritation from mould toxins. Offering ice cubes or wet food can soothe her throat until the irritation passes.
The full verdict, portion guidance and serving notes are collected on the Sugar food facts page.