Cat Urinating a Lot and Drinking a Lot: Causes and When to Test

By Dr. Zubair Khalid, DVM, MS, PhD · 2026-08-14

Key Takeaways

• Increased thirst (polydipsia) and urination (polyuria) in cats are significant clinical signs, not diseases themselves, indicating underlying systemic issues that require prompt veterinary investigation.
• Emergency situations warrant immediate veterinary intervention, characterized by straining to urinate with little to no output, vocalization during urination, vomiting, collapse, pale gums, or labored breathing, as these can indicate life-threatening conditions like a blocked bladder.
• Common differential diagnoses for polyuria/polydipsia include chronic kidney disease, diabetes mellitus, and hyperthyroidism, each with distinct pathophysiological mechanisms and management strategies requiring diagnostic confirmation.
• Diagnostic workup typically involves a physical examination, blood panel (evaluating kidney function, glucose, thyroid hormones, liver enzymes), and urinalysis (assessing urine concentration, presence of glucose, protein, and signs of infection).
• Never restrict water intake in a cat exhibiting increased thirst; instead, ensure constant access to fresh water and avoid home-based treatments or dietary changes prior to veterinary diagnosis, as these can interfere with diagnostic accuracy and potentially harm the cat.
• Proactive veterinary wellness exams, particularly twice-yearly for senior cats, are crucial for early detection of conditions like chronic kidney disease and diabetes through routine blood and urine screening, significantly improving prognosis and quality of life.

If your cat is drinking more water than usual and peeing more often, you are right to pay attention. These two signs often appear together, and in veterinary medicine they have a formal name: polyuria and polydipsia, or PU/PD for short. Polyuria means increased urine production, and polydipsia means increased thirst. This combination is not a disease itself. It is a clue that something else is going on inside your cat's body.

Most causes of increased thirst and urination are treatable, especially when caught early. But some causes can become dangerous quickly. Please read the emergency signs below first, because a small number of cats with these symptoms need immediate care. If your cat does not show those emergency signs, you still should not wait long. A same-day veterinary visit is the safest choice for most cats with this pattern.

Is This an Emergency?

Some cats with increased thirst and urination have a blocked bladder or kidney failure. Both can be life-threatening within hours. Use this table to decide how fast to act.

{
 "type": "triage",
 "title": "Urgency triage by severity of signs",
 "tiers": [
  {
   "tier": "danger",
   "label": "Go to an emergency vet now",
   "signs": [
    "Your cat is straining to urinate but produces little or no urine",
    "Your cat cries out when trying to pee",
    "Your cat is vomiting, very weak, or collapses",
    "Your cat's gums are pale or gray"
   ],
   "action": [
    "Do not wait for a regular appointment",
    "Call the nearest emergency veterinary hospital and go immediately",
    "A blocked bladder is a medical emergency that can be fatal within 24 to 48 hours"
   ]
  },
  {
   "tier": "warn",
   "label": "Book a same-day appointment",
   "signs": [
    "Your cat is drinking and peeing noticeably more than usual but otherwise seems alert and active",
    "Your cat is urinating outside the litter box",
    "Your cat has lost weight despite a normal or increased appetite",
    "Your cat seems more tired than usual"
   ],
   "action": [
    "Call your regular veterinarian this morning and ask for the earliest available appointment",
    "Do not wait to see if it resolves on its own"
   ]
  },
  {
   "tier": "safe",
   "label": "Can be watched at home for a defined period",
   "signs": [
    "Your cat had one day of slightly increased thirst after eating a very salty treat or after vigorous play in hot weather",
    "Your cat is otherwise eating, playing, and behaving normally"
   ],
   "action": [
    "Watch closely for 24 hours",
    "Measure how much water your cat drinks each day and note how often the litter box needs changing",
    "If the increase continues past 24 hours, book a veterinary appointment"
   ]
  }
 ]
}

If you are unsure which category fits your cat, choose the faster option. It is always safer to have a veterinarian examine your cat and find nothing serious than to wait and miss a treatable problem.

What Is Most Likely Going On

The most common causes of increased thirst and urination in cats fall into a few main groups. Your veterinarian will consider these first.

Chronic kidney disease is very common in older cats. The kidneys normally filter waste from the blood and concentrate urine to save water. When kidney function declines, the kidneys cannot concentrate urine properly. The cat produces large amounts of dilute urine, loses water, and drinks more to compensate. This condition develops slowly and is manageable with diet and medication, but it cannot be reversed. Early diagnosis gives your cat the best chance at a good quality of life.

Diabetes mellitus is another frequent cause, especially in middle-aged and overweight cats. In diabetes, the body cannot use sugar from food properly because of a problem with insulin. Sugar builds up in the bloodstream and spills into the urine. The sugar pulls water with it, so the cat produces large volumes of urine and drinks constantly. Many diabetic cats also eat more but lose weight. With treatment, often including insulin injections, many cats improve dramatically.

Hyperthyroidism occurs when the thyroid gland produces too much thyroid hormone. This speeds up the cat's metabolism. Affected cats often drink and urinate more, eat a lot, and lose weight. They may also be restless or vocal. This condition is very treatable with medication, diet, radioactive iodine therapy, or surgery.

What Else It Could Be

Several other conditions can cause the same signs. Some are less common but still important.

Urinary tract infection can cause increased urination, though cats with infections often show other signs too, such as straining, blood in the urine, or urinating outside the box. Infections are treatable with antibiotics, but the specific antibiotic must be chosen by a veterinarian based on testing.

Liver disease can affect thirst and urination in some cats. Liver problems may also cause jaundice, which is a yellow tint to the gums, eyes, or skin, along with poor appetite and vomiting.

Electrolyte imbalances, such as low potassium or high calcium, can cause increased thirst and urination. These imbalances have many possible underlying causes, and blood testing is needed to identify them.

Certain medications, especially steroids like prednisolone, can increase thirst and urination as a side effect. If your cat recently started a new medication, tell your veterinarian.

Psychological or behavioral factors are possible but far less common. Some cats drink more due to stress or boredom, but a veterinarian should rule out medical causes first before assuming a behavioral reason.

Why Testing Matters

You cannot tell which cause is affecting your cat just by watching. The signs overlap heavily between conditions. A cat with kidney disease and a cat with diabetes can look identical at home. Only testing can separate them.

Your veterinarian will likely recommend a physical examination, a blood panel, and a urine test. The blood panel checks kidney values, blood sugar, thyroid hormone, and liver enzymes. The urine test checks concentration, sugar, protein, and signs of infection. These tests are quick and give your veterinarian the information needed to start the right treatment.

Do not try to treat this at home without a diagnosis. Giving your cat extra water is fine, but changing food, adding supplements, or withholding water can be harmful. Water should never be restricted, because a cat that cannot urinate or that has kidney failure can become dangerously dehydrated.

The sooner you get an answer, the sooner your cat can feel better. Many cats with these conditions respond well to treatment and live comfortably for years. The first step is a simple veterinary visit, and that visit should happen today.

What You Can Do at Home Right Now

If your cat is drinking and peeing more than usual, there are safe things you can do while you arrange a veterinary visit. Do not restrict your cat's water. A cat that is drinking a lot needs that water to avoid dehydration. Keep every bowl full and clean. If you have multiple cats, add extra water bowls in different rooms so the thirsty cat always has access.

Do not change your cat's food suddenly. Do not give any medication, including over-the-counter products, unless your veterinarian has told you to. Some human pain relievers are toxic to cats. Never guess at a dose for a cat. Dosing must come from the treating veterinarian because it depends on your cat's weight, kidney function, and the specific drug involved.

Watch your cat's litter box habits closely. If your cat is straining to urinate, crying in the box, or producing no urine at all, that is an emergency. A blocked bladder is life-threatening and requires immediate in-person care. Do not try to manage this at home or through a remote consultation.

What to Write Down Before You Call

A few minutes of observation will help your veterinarian give you better advice. Write down these details:

• How much water your cat drinks in 24 hours. Use a measuring cup to fill the bowl, then measure what is left the next day.
• How many times your cat uses the litter box in a day.
• Whether each urine clump is large, small, or normal sized.
• Whether your cat seems to strain or cry when urinating.
• Whether your cat is urinating outside the box, and where.
• Your cat's appetite. Is it normal, increased, or decreased?
• Your cat's weight, if you can weigh them at home.
• Any vomiting, diarrhea, or changes in energy level.
• Any medications or supplements your cat receives.

Symptom Tracking Chart

Use this chart to record daily observations. Bring it to your appointment.

What the Veterinary Visit Usually Involves

Your veterinarian will start with a physical exam. They will feel your cat's abdomen to check the kidneys and bladder. They will listen to the heart and lungs. They will check your cat's hydration by feeling the skin and gums.

The veterinarian will ask about your cat's history. Expect questions about water intake, urine output, appetite, weight change, and any other signs you have noticed. Bring your tracking chart.

Testing is the core of this workup. The two most common tests are:

• Bloodwork. This checks kidney values, blood sugar, thyroid hormone, and other markers. It can separate kidney disease from diabetes from hyperthyroidism.
• Urinalysis. This checks urine concentration, sugar, protein, and signs of infection. It is often done alongside bloodwork.

Other tests may include blood pressure measurement, urine culture, or imaging like ultrasound. These are added when the first tests do not give a clear answer.

Cost varies widely by region and clinic. A basic blood panel and urinalysis might fall in a range that feels like a moderate expense, while adding ultrasound or a urine culture can raise the total noticeably. These are general ranges only. Ask your clinic for an estimate before testing. Many clinics offer a written estimate you can approve first.

When an Online Vet Can Help, and When It Cannot

Some situations in this article require hands-on care and must not be handled remotely. A cat that is straining to urinate with little or no output needs emergency in-person care immediately. A cat that is vomiting repeatedly, collapsed, or breathing fast at rest also needs in-person care. A cat with a distended, painful belly cannot be assessed by video. Do not use a remote consultation for these signs.

A remote consultation is genuinely useful in other situations. If your cat has a mild increase in thirst that started recently, an online vet can help you decide whether a visit is needed. If your cat has a known condition like early kidney disease, a remote recheck can review trends and answer questions. If you are unsure whether a sign warrants a visit, a remote vet can triage that decision. If your cat started a new medication and you wonder about side effects, that is a reasonable remote question.

A remote veterinarian can take a detailed history, look at visible signs on video, and advise you. In many states they can prescribe. But they cannot palpate the abdomen, listen to the chest, take a temperature, run bloodwork, or image anything. Those limitations matter for this problem. Increased thirst and urination cannot be diagnosed without lab work. Prescribing rules differ by state, and a veterinarian may require an in-person examination before prescribing for a new problem.

Your Vet Diagnostic Checklist

Bring this checklist to your appointment or use it to prepare for a call.

• [ ] Tracking chart with at least 2 to 3 days of water and urine records
• [ ] List of all medications and supplements
• [ ] Current weight, if known
• [ ] Notes on appetite and vomiting
• [ ] Any urine samples collected as instructed by your vet
• [ ] Questions you want to ask about testing options and costs

What Happens After Testing

Once the results come back, your veterinarian will explain what is driving the thirst and urination. Diabetes, kidney disease, and hyperthyroidism each have different treatment plans. Some conditions are managed with diet, others with medication, and some with both. The MSD Veterinary Manual Pet Owner Version explains these conditions in plain language and can help you understand your cat's diagnosis. The American Veterinary Medical Association also offers guidance on working with your veterinarian and managing chronic conditions.

Treatment is not a one-size-fits-all plan. Your cat's age, other health problems, and test results all shape the approach. Ask your veterinarian what to expect in the first week, what signs should prompt a call, and when the next recheck should happen. With a clear diagnosis and a consistent routine, many cats with these conditions live comfortably for years.

Common Mistakes Owners Make With This Problem

Many owners unintentionally delay diagnosis or make the problem harder to read. Here are the most frequent errors and the better approach.

The most costly mistake is waiting for other signs like weight loss or vomiting. By then, the underlying disease is further along. Testing early gives you more options.

How to Reduce the Chance of It Happening Again

You cannot prevent every cause of increased thirst and urination. Some conditions have a genetic component. But you can lower the risk and catch problems earlier.

Keep your cat at a healthy weight. Obesity is a major risk factor for diabetes in cats. Ask your vet what body condition score your cat should have and how many calories to feed per day.

Provide fresh water in multiple locations. Some cats drink more when water bowls are clean and placed away from the litter box. A cat fountain can encourage drinking, which supports kidney health.

Schedule wellness exams at least once a year. For cats over seven years old, twice a year is better. Routine blood work and urine tests can catch kidney disease or diabetes before you notice symptoms. The American Veterinary Medical Association recommends regular preventive care as the foundation of catching problems early. See their pet owner resources on preventive health for guidance on visit frequency.

Keep the litter box clean and count how often you scoop. A sudden change in urine volume is easier to spot when you have a baseline. If you have multiple cats, use separate boxes so you can tell which cat is affected.

What Recovery and Ongoing Management Usually Look Like

Recovery depends entirely on the cause. There is no single timeline that fits every cat.

For diabetes, treatment usually starts with insulin injections twice daily and a consistent feeding schedule. Most cats improve within two to four weeks of starting insulin. Some cats enter remission, meaning they no longer need insulin, especially if treatment starts early. Others need lifelong injections. Your vet will teach you how to give injections at home and how to monitor blood glucose.

For chronic kidney disease, there is no cure. Management focuses on slowing progression. This includes a kidney-friendly diet, medications to control blood pressure and nausea, and sometimes fluid therapy under the skin. You may see improvement in thirst and energy within a few weeks of starting treatment. The disease is progressive, so regular rechecks every three to six months are typical.

For hyperthyroidism, treatment options include medication, a special diet, radioactive iodine therapy, or surgery. With medication, you may see less drinking within one to two weeks. Radioactive iodine can cure the condition in many cats.

For a urinary tract infection, antibiotics usually improve signs within a few days. Finish the entire course even if your cat seems better.

For conditions like cancer or liver disease, the outlook varies widely. Your vet will give you a realistic picture based on test results.

Ongoing management always includes regular monitoring. Expect follow-up blood tests, urine tests, and weight checks. Keep a log of how much your cat drinks and urinates between visits. This information helps your vet adjust treatment.

Frequently Asked Questions

How much water is too much for a cat?

A normal cat drinks about 3.5 to 4.5 ounces of water per 5 pounds of body weight per day. That is roughly half a cup for a 10 pound cat. If your cat drinks more than that consistently, or if you are refilling the bowl much more often than usual, mention it to your vet. Measuring daily water intake for three days before the visit gives your vet useful data.

Can stress cause a cat to drink and pee more?

Stress can contribute to some urinary issues, but it is not a common cause of true increases in thirst and urine volume. Conditions like diabetes and kidney disease are far more likely. Do not assume stress is the cause without testing. Your vet can rule out medical problems first, then discuss environmental factors.

Will my cat need to stay at the hospital?

Many cats can be diagnosed and treated as outpatients. Blood and urine tests take minutes. If your cat is severely dehydrated, has diabetic ketoacidosis, or has advanced kidney failure, a hospital stay of one to three days may be needed for fluids and monitoring. Your vet will tell you if hospitalization is necessary.

How much will the tests cost?

Costs vary widely by region and clinic. A basic blood panel and urinalysis often range from 150 to 400 dollars. Additional tests like blood pressure, ultrasound, or hormone assays add more. Ask your clinic for an itemized estimate before testing. Many clinics offer payment plans or pet insurance can help cover the cost.

Can I manage this with diet alone?

Diet is part of treatment for many conditions, but it is rarely the only treatment. Diabetes may require insulin. Kidney disease may need medications and fluids. Hyperthyroidism may need medication or radioactive iodine. Never change your cat's diet without veterinary guidance, as the wrong food can worsen some conditions.

What if my cat stops drinking or peeing suddenly?

A sudden stop in urination is an emergency. It can indicate a blocked urethra, which is life-threatening. Seek in-person emergency care immediately. Do not wait and do not try home remedies. A cat that stops drinking and eating also needs urgent veterinary attention.

Related Clinical & Scientific Guides

• Cat Straining to Poop but Only Passing Mucus: Causes and Care
• Cat Upset Stomach: Home Remedies That Are Safe
• Cat Straining to Poop but Nothing Comes Out: Emergency or Not?

References and Further Reading

• MSD Veterinary Manual Digestive Disorders of Dogs and Cats
• AVMA Pet Owner Resources
• MSD Veterinary Manual Pet Owner Version
• AAHA Pet Owner Resources

Related Articles

• Cat Urinating Frequently: Causes and When to Worry
• Cat Vomiting After Drinking Water: Causes and When to Worry
• Cat Diarrhea with Mucus: Causes and When to Worry
• Cat Vomiting at Night: Causes and When to Worry
• Cat Blood in Urine: Causes and When to Rush to the Vet

This article is general educational information for pet owners. It is not a substitute for veterinary diagnosis, examination, or treatment. If your pet is showing severe or rapidly worsening signs, contact an emergency veterinary hospital immediately.