I am always concerned when an owner tells me their cat "drinks and urinates well" as this can be a 'red flag' that there is an underlying medical issue. The most common causes in older cats are kidney failure, hyperthyroidism, diabetes or an infection in the urinary system. Younger cats are more prone to urinary tract infections and/or crystals in the urine causing this although we do still see some with kidney failure or diabetes. Less commonly, liver issues may cause these symptoms. It is possible for more than one of the above issues to be happening at the same time as diabetes leaves them immune compromised and more prone to infections.
As a species, cats were not designed to eat foods high in carbohydrates (sugars) and ALL dry formulas are, as are many canned ones. Carbohydrates are necessary for the extrusion process to make the dry kibble which is why dry formulas are so high. Many owners are surpised to also find out that dry food is more processed than canned food. The canned food has a higher water content which is beneficial for cats and their kidneys. If on a dry diet, you will usually see them drink more due to the lack of water content in the food.
If you average cat (8-12 lbs or 3.5 - 5.5 kg) is urinating more than two fist sized clumps in the litterpan in 24 hours I recommend having them checked out. Some healthy/normal cats will produce more than this, but it is a good idea to get them in, check their blood glucose and kidney values and have their urine examined to ensure they are concentrating it, that there is no glucose in it and no infection present.
If diabetes is present and remains unregulated it can lead to many debilitating issues some of which include chronic urinary tract infections, neuropathy that typically affects the way they stand on their hind feet (drop-hocked or flat footed), decreased energy and diabetic ketoacidosis, a lifethreatening emergency.
Here is a link to a video on our Facebook page of a cat with diabetic neuropathy affecting the hind feet: https://www.facebook.com/Atlantic-Cat-Hospital-520776717950363/
If diabetes is caught early your cat has a good chance of going into remission, sometimes with a diet change alone. The longer it goes unchecked the less likely this will happen.
For more information on diabetes in cats visit: http://binkyspage.tripod.com/index.html
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