An excessive volume of urination for an adult is more than 2.5 liters (about 67 fluid ounces or about 2.6 quarts) of urine per day. However, this can vary depending on how much water you drink and what your total body water is. This problem is different from needing to urinate often.

Polyuria is a fairly common symptom. People often notice the problem when they have to get up during the night to use the toilet (nocturia).

Some common causes of the problems are:

• Diabetes insipidus
• Diabetes mellitus
• Drinking excessive amounts of water

Less common causes include:

• Kidney failure
• Medicines such as diuretics and lithium
• High or low calcium level in the body
• Drinking alcohol and caffeine
• Sickle cell anemia

Also, your urine production may increase for 24 hours after having tests that involve injecting a special dye (contrast medium) into your vein during imaging tests such as a CT scan or an MRI scan.

To monitor your urine output, keep a daily record of the following:

• How much and what you drink
• How often you urinate and how much urine you produce each time
• How much you weigh (use the same scale every day)

Contact your health care provider if you have excessive urination over several days, and it is not explained by medicines you take or drinking more fluids.

Your provider will perform a physical exam and ask questions such as:

• When did the problem start and has it changed over time?
• How often do you urinate during the daytime and overnight? Do you get up at night to urinate?
• Do you have problems controlling your urine?
• What makes the problem worse? Better?
• Have you noticed any blood in your urine or change in urine color?
• Do you have any other symptoms (such as pain, burning, fever, or abdominal pain)?
• Do you have a history of diabetes, kidney disease, or urinary infections?
• What medicines do you take?
• How much salt do you eat? Do you drink alcohol and caffeine?

Tests that may be done include:

• Blood sugar (glucose) test
• Blood urea nitrogen test
• Creatinine (serum)
• Electrolytes (serum)
• Fluid deprivation test (limiting fluids to see if the urine volume decreases)
• Osmolality blood test
• Urinalysis
• Urine osmolality test
• 24-hour urine test

Polyuria

Elsamra SE. Evaluation of the urologic patient: history and physical examination. In: Partin AW, Domochowski RR, Kavoussi LR, Peters CA, eds. Campbell-Walsh-Wein Urology. 12th ed. Philadelphia, PA: Elsevier; 2021:chap 1.

Gharavi AG, Landry DW. Approach to the patient with renal disease. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 100.

Updated by: Kelly L. Stratton, MD, FACS, Associate Professor, Department of Urology, University of Oklahoma Health Sciences Center, Oklahoma City, OK. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.