Why Does My Cat Drink So Much and Pee So Often? Causes of Increased Thirst and Urination in Cats

Thoughtful Cat

There are a number of illnesses that can trigger excessive thirst (polydipsia) and urination (polyuria) in cats.

Cats with polydipsia may drink from the shower, toilet, tub, sink faucets, or plant trays. Their litter boxes require scooping more often due to increased urination and their water bowls have to be refilled more frequently than in the past. Of course, many healthy cats drink from faucets and toilets, and normal water consumption and urination vary from one cat to the next. It’s changes in a cat’s habits that usually indicate a problem.

Illnesses That Cause Excessive Thirst and Increased Urination in Cats

The illnesses that most often trigger frequent urination and increased thirst in cats are:

    • Kidney disease (also known as chronic renal failure or CRF)
    • Diabetes mellitus
    • Thyroid disease (hyperthyroidism)

These three diseases are common in older cats, and the latter two also cause increased appetite. Other illnesses and illness symptoms that can cause polydipsia and polyuria (some of which are quite rare) include the following.

Electrolyte Abnormalities

Electrolyte abnormalities that can affect drinking and urination include:

    • Low blood potassium (hypokalemia), typically resulting from symptoms of underlying illness, such as appetite loss, vomiting, or diarrhea
    • High blood calcium (hypercalcemia), often due to a tumour, kidney disease, or other health problem

Endocrine (Hormonal) Disorders

Endocrine problems that can cause increased thirst and urination in cats include:

    • Acromegaly, a condition whereby too much growth hormone is released into the system, often caused by a benign pituitary tumour
    • Central diabetes insipidus, which may be triggered by head trauma, pituitary gland tumour, or unknown causes
    • Hyperadrenocorticism (Cushing’s disease), usually caused by a benign pituitary tumour
    • Hypoadrenocorticism (Addison’s disease), which can have a variety of different causes, the most common of which is autoimmune reaction (the body’s immune system attacking its own tissues)

Additional Causes of Increased Urination and Thirst in Cats

Miscellaneous triggers for polyuria and polydipsia in cats include:

    • High red blood cell count (polycythemia), a symptom of many different illnesses
    • Kidney infection (pyelonephritis)
    • Liver disease
    • Renal glycosuria, a kidney disorder caused by a disease or congenital defect
    • Uterine infection (pyometra)

Treatment for polydipsia and polyuria varies based on the underlying cause.

Non-Illness-Related Causes of Increased Urination and Thirst in Cats

Non-illness-related polydipsia and polyuria triggers include:

    • Administration of diuretics, salt, or certain medications
    • Hot temperatures
    • Increased exercise
    • Post-obstructive diuresis (increased urination after removal of a urinary obstruction)
    • Switch from wet food to dry (many cats on dry-food-only diets are chronically dehydrated)

Psychogenic polydipsia, an extremely rare obsessive-compulsive behavioural problem, can also cause excessive fluid consumption. Treatments for this condition may include behaviour modification therapy and gradual water restriction. In severe cases, a veterinarian may prescribe medications designed to reduce obsessive-compulsive behaviours.

Symptoms of Illness That May Accompany Polydipsia and Polyuria in Cats

Additional symptoms that suggest polydipsia and polyuria are due to a medical problem include:

    • Behavioural changes
    • Constipation
    • Diarrhea
    • Having accidents outside the litter box
    • Increased appetite
    • Lethargy
    • Loss of weight and/or appetite
    • Poor coat condition
    • Vomiting
    • Weakness

If you notice a change in your cat’s drinking or urination habits, consult a veterinarian.

For more cat articles, see the main Cats page.


    • Bennett, P., BVSc, FACVSc, DipACVIM. (2003). Polyuria and Polydipsia [PDF]. Australian College of Veterinary Scientists – Science Week 2003 – Small Animal Medicine Chapter Meeting.
    • Fenner, W.R., et al. (2000). Quick Reference to Veterinary Medicine, Third Edition. Baltimore, MD: Lippincott Williams & Wilkins.
    • Lappin, M.R., DVM, PhD. (2001). Feline Internal Medicine Secrets. Philadelphia, PA: Hanley & Belfus Inc.
    • Melin, E., DVM., Westgate Pet Clinic. (n.d.). “What is Polyuria/Polydipsia? AKA: Why is My Pet Drinking and Urinating so Much?” WagsandWhiskers.com.
    • Osborne, C.A., DVM, PhD, DiplACVIM. (1 June 2003). “ The Ins and Outs of Polyuria and Polydipsia.” DVM360. VeterinaryNewsDVM360.com.
    • PetMD.com. (n.d.). “Increased Thirst and Urination in Cats.”
    • Petplace Veterinarians. (2011). “Polydipsia and Polyuria (Excessive Drinking and Urinating) in Cats.” PetPlace.com.

2 thoughts on “Why Does My Cat Drink So Much and Pee So Often? Causes of Increased Thirst and Urination in Cats”

  1. I have never heard of this happening with recommended use, but ingesting Feliway may cause illness in cats. Cats are meant to inhale the scent; not consume the Feliway fluid. Feliway shouldn’t be sprayed directly on cats because they will lick it off. If the cat hasn’t ingested any Feliway, the cause is more likely illness or ingestion of another toxic substance. If your cat is showing signs of illness, I recommend consulting a veterinarian to check for conditions such as diabetes and to rule out poisoning.

  2. I promise to solve your issue 100%
    Stay away from all dry food and any commercial brands like Friskies, Purina etc. I use to give only dry and now my three cats get a raw diet with very little dry on top.
    I buy RadCat (comes frozen) but there are other brands as well. I completely stop the urine problem since one of my cats would not drink water. He now gets plenty of moisture in the raw food. There coats look shiny, less cat fur, no more unrinating problems since the raw was slowly introduced. It only took a few days for them to now crave it.
    When a cat only eats dry and tends not to drink water (some cats don’t drink water) then you will have urination issues and possible vet visits. The raw contains lots of mositure enough for the cat and everything a cat needs. rememeber cats are carnivors not herbavores or omnivors.
    I tend to give a tablespoon of raw and a quarter tablespoon of dry on top (good dry food like Orajen, Wellness core etc). I then add an extra tablespoon of water.
    I have not had an issue in years.
    Let me repeat : Problem gone for several years No issue anymore. My cat urinates normally.
    But the Raw Frozen (any good brand at a natural pet store) and you will solve the problem 100%. They may be reluctant to eat it at first (slowly introduce) but will love it and love and crave it everyday. They run to the bowl when its feeding time.
    here are a few links:

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