Yes — safe in moderation
Yes — plain pumpkin is a vet favourite. A spoonful of pure cooked or tinned pumpkin can ease both mild diarrhoea and constipation thanks to its soluble fibre.
Plain pumpkin (fresh cooked or 100% pure tinned — not pie filling) is low in calories and high in soluble fibre, which absorbs excess water in loose stools and adds bulk to firm things up when a dog is constipated. It is also rich in vitamin A and gentle on sensitive stomachs, which is why so many owners keep a tin in the cupboard. Avoid pumpkin pie filling, which contains sugar and spices like nutmeg that are not good for dogs.
One to four teaspoons mixed into food per day depending on size — start small. As a digestive aid it is wonderfully effective, but if diarrhoea or constipation lasts more than a day or two, see your vet rather than relying on pumpkin alone.
Plain sweet potato offers similar fibre; for protein try eggs.
General information, not veterinary advice. If your pet has eaten something potentially harmful or shows symptoms, contact your vet or an emergency clinic immediately. Full disclaimer.