Why is my cat loosing weight and drinking more water?

Our question this week was:

Hi Dr. Debra, I have two 14-year-old cats. But the boy seems too be sicker that the girl cat. He is old and losing weight. I can tell because they both are VERY BIG cats. I can now feel his spine. They both seem to be drinking a lot of water. I keep three to three bowls out and I keep refilling them.

My boy cat suddenly started drinking from the toilet and claiming into the shower after we get out looking for water. I can’t figure it out. I leave plenty of clean water out for them. He also suddenly became very picky about his favorite food. And he seems to sleep more offend. Is this a sign that he may be a diabetic? Or is it something else? Please help me figure this out. I will take him to his vet. But I just want a few other options.




Hi Lisa– thanks for your email. You wrote that your male 14-year-old cat is losing weight, seems to have increase thirst and a decreased appetite. He also seems to sleep more.

I’d recommend that you take him to your veterinarian for evaluation. They will probably want to run some basic blood work (complete blood count [CBC]), diagnostic profile, thyroid level (T4), and a urinalysis.

This will help look for some common causes of his symptoms including diabetes mellitus, hyperthyroidism and kidney disease.

If your other cat is sick, it may be worth also having her checked out. If you have a chance, click on the links above to learn more about these disease. Another article that might be useful is called Polydipsia and Polyuria in Cats. It discusses common reasons why cats might drink more.

Best of luck!

Dr. Debra

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