My dog scratches and chews his paws all night — is it a food allergy?

Probably not food — or rather, food is the last thing to test, not the first, and jumping straight to it is the most common wrong turn owners take.

Itch is a symptom, and it has an order of investigation. Parasites come first, because fleas and mites can make a dog frantically itchy with nothing visible on the coat: a single flea is enough in a sensitised dog, and mites live in the skin rather than on it. Your vet will want that ruled out properly before anything else, and it is also the cheapest step. Then the pattern tells the story. Paws, ears, armpits, groin and belly is the classic environmental-allergy map, and the timeline matters enormously — itch that flares in one season points one way, year-round itch points another. Food-responsive itch tends to be non-seasonal and often involves the ears and the back end.

A food trial only counts if it is done properly: a diet chosen with your vet, run for the full period, with zero treats, zero flavoured chews, zero table scraps and zero flavoured medications. A half-done trial answers nothing and wastes weeks.

Concretely, before the appointment: comb him with a flea comb over a damp white paper towel and look for black specks that smear rust-red — that is digested blood, and it is proof. Photograph the skin and the undersides of the paws (are they stained brown from licking?). Keep a simple diary: the date, and an itch score from 0 to 10. That timeline is honestly the most useful thing you can hand your vet.

Be seen urgently, the same day, if there are raw weeping sores, a strong yeasty smell, or sudden hives with a swollen face or muzzle.