My cat has a swollen lip

My five-year-old cat has developed an odd-looking swelling on their lower lip. It looks red but doesn't seem to bother them at all. Should I see a vet? And can you advise on a cause?

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A All vets, and doctors for that matter, prefer to see problems at an early stage. This always makes diagnosis and effective treatment much easier.

Chin lesions in cats are not uncommon and there are two main conditions. Acne is well-recognised with black spots called comedones, with redness being less obvious. Your cat may have the other condition, called eosinophilic granuloma. This is a description of its pathology rather than a diagnosis, and several versions exist.

Apart from chin lesions, eosinophilic granulomas may have thickened lines (linear) down the backs of the thighs, lesions on the tongue and soft palate, and plaque-like lesions on the inside of the thighs.