Weight loss worry

Minette has lost weight - despite a raging appetite. She has also been a lot more talkative than usual. Her owners are (and Dr Kate) are suspicious that she might have hyperthyroidism. Minette very kindly let us take a sample of blood - you can see the hair under her collar was clipped so we could see her vein.
Minette is about 20 years old and very fit for her age. She is on medication for high blood pressure and has kept her kidney disease at bay with a special diet for over a year. Her owners' vigilance and care should keep her going for a few birthdays yet!

Weight loss is not always good...

You might think that vets are obsessive about recording cats’ weights. They have good reason – sometimes gradual weight loss is the only sign of serious disease in cats. By the time a cat goes off her food or starts vomiting disease can be quite advanced.
Fur or hair ball vomits coupled with gradual weight loss indicate gastrointestinal disease. Causes of gut disease include parasites like worms and giardia. These are easy to diagnose and treat compared to other gut diseases.
Food sensitivities are uncommon but inflammatory bowel disease and bowel cancer occur relatively often in cats. Diagnosing and treating these can be quite a challenge and require much patience on the part of owner and vet.
A myriad things cause weight loss with a patchy appetite. We will nearly always order blood tests to check for kidney or liver disease, particularly in older cats.
Weight loss despite a good appetite can be due to diabetes or an overactive thyroid (hyperthyroidism). Annual check-ups and weigh-ins in cats under 10 years pick these problems up early. Cats over 10 years of age should be checked at least twice a year. With appropriate treatment affected cats go on to live long and happy lives.
Even if your cat is aiming to lose weight regular weigh-ins and veterinary supervision are essential. We want gradual loss of weight because rapid weight loss in cats can lead to liver disease.

George's spectacular appetite

My cat George was always hungry.  When he was young we called him Fat George.  As he aged he became thinner and thinner.  When he was 12 years old I noticed that his activity levels as well as his appetite were reaching record levels.
At first I thought he'd reverted to kittenhood but soon found that one of the thyroid glands on the lower part of his neck was as big as a lima bean.  A blood test confirmed the diagnosis of hyperthyroidism.
I surgically removed the gland and he was normal for a few years before I noticed his appetite rocket again.  This time I medicated him with an anti-thyroid drug that worked very well.  I gave him a tablet twice a day until he became too cunning for me. I switched to applying a medicated gel to the inside of his ears and won the battle.
Like most old cats George eventually developed kidney disease.  I had to ease off the antithyroid medication and nurse his old kidneys along.
This candid shot is of George not long before he died.  Even when his kidneys were about to collapse his overactive thyroid drove his appetite to spectacular heights (depths?!)