Cat Drinking Too Much Water? Excessive Drinking Explained

If you notice that your cat is suddenly drinking too much water you should seek medical advice. Excessive drinking is a symptom for many serious diseases starting from diabetes to kidney failure.

Diabetes Mellitus

Diabetes mellitus is caused by a deficit of insulin of by the incapacity of the body to properly assimilate glucose. One of the symptoms of diabetes is increased thirst and urination. Other symptoms of diabetes include:

  • Improved appetite
  • Weight loss
  • Panting
  • Foul smelling breath
  • Dehydration
  • Vomiting
  • Lethargy

Diabetes needs to be detected and may be managed with daily shots of insulin. If left untreated, it may lead to cataracts and blindness.

Kidney Failure

Kidney failure, also known as uremic poisoning is a serious medical condition. In case of kidney failure, the kidneys cannot function properly and are not able to process and remove the waste from the body.

Kidney failure may be caused by a number of factors such as aging, urinary tract blockage, poisoning, shock, blocked arteries, a blood clot or an infection.

Other symptoms of kidney failure include:

  • Spraying
  • Increased urination
  • The surface of the tongue is brownish
  • Weight loss
  • Lack of appetite
  • Vomiting
  • Diarrhea

Depending on the cause of kidney failure, there are several treatment options. However, if the condition is left untreated, it may be fatal.


Glomerulonephritis is an inflammatory disease affecting the kidneys. The kidneys are not able to properly filter blood. A lot of essential substances are lost including protein and the condition may be lead to kidney failure which may be fatal for the cat.

Other symptoms of glomerulonephritis include:

  • More frequent urination
  • Lethargy
  • Lack of appetite
  • Weight loss
  • Difficulty in breathing
  • Swelling of the face, abdomen and the rectal area
  • Vomiting

Glomerulonephritis may be caused by infections, cancer, feline leukemia virus, or feline AIDS.


Amyloidosis is an insufficiency of protein metabolism. The proteins may be deposited in the cat's kidneys and other vital organs and may lead to kidney failure or the failure of the affected organs. Amyloidosis is a rare condition, but is very severe. Make sure you notice other symptoms of this disease:

  • Frequent urination
  • Impurities in the urine caused by high levels of eliminated protein
  • Swelling of face and abdomen
  • Lack of appetite
  • Weight loss
  • Nausea and vomiting
  • Breathing difficulty

If detected in timely manner, the condition may be treated.


Hyperthyroidism may also cause increased thirst. If the thyroid gland is overly active, the cat may also experience weight loss, greasy skin, acne, vomiting and diarrhea and behavioral changes.

Should your cat start to suddenly drink more water, you need to bring him to the vet. Try to monitor the amounts of water your cat drinks on a daily basis. A urine sample is needed to determine the cause of increased thirst. The urine concentration is among the tests that your vet will carry out to diagnose your pet.