Why is our cat losing weight?

QMy 12-year-old male neutered domestic shorthaired cat has lost weight, despite still eating well, in fact more than usual. I have checked on the internet and it is suggesting an overactive thyroid gland. Is this a common problem and is it urgent?

AOvereating, yet losing weight, are certainly signs of an overactive thyroid gland (hyperthyroidism). It is common, affecting about 10 per cent of cats over the age of 10 years, and the symptoms you mention are the two most common ones. Hyperthyroid cats may also drink more, have a racing pulse and can become uncharacteristically irritable. This can make them difficult to examine sometimes, but if they allow handling without aggression it is possible in around 80 per cent of cats to feel the enlarged thyroid glands in the neck. Hyperthyroidism is not an emergency while the cat continues to eat and is otherwise well. However, it is definitely worthwhile calling the vet to arrange a physical examination and blood tests, which will usually give a diagnosis. Hyperthyroidism will not go away on its own and if there is a delay in seeking help there are several complications that will occur, such as heart and kidney problems. As with most diseases early diagnosis and treatment has the best prognosis. Treatments either aim to cure, such as radioactive iodine and thyroid removal, or control, including anti-thyroid drugs and iodine-restricted diets. These treatments have advantages and disadvantages, but have a generally good outlook, especially in the initial stages when complications have not yet occurred.

QMy three-year-old West Highland white female neutered dog developed an itch last year. It affected the eyes and feet especially from February until May and my vet treated her for an allergic condition. Is it likely to happen again this year and what can be done to prevent it?

AWest Highland whites are prone to an allergic condition called atopic dermatitis (atopy). This has many similarities to hay fever in people, with allergy to pollens and house dust common causes. In dogs the skin is predominantly involved, rather than hay fever signs involving the eyes and nose that usually affect us. Atopic dogs usually rub the skin around the eyes, scratch the ventral abdomen, lick their paws, and have recurrent ear problems, although not necessarily all four signs in all cases. Your dog has shown seasonal signs that suggest allergy to tree pollens could be the problem. Tree pollens are prevalent, at least in the London region, from the middle of February and have largely disappeared by the middle of May. Unfortunately for hay fever sufferers, and some dogs, grass pollens take over then until the end of July. If your dog is atopic, which seems very likely, you can expect the problem to resurface about the same time as last year. For a season lasting three months, anti-inflammatory drugs may be all that are required to treat symptoms. If further allergies develop there are various long-term options, including desensitising injections, which will keep the dog comfortable.