Normally, urine decreases in amount and become more concentrated at night. That means, most people can sleep 6 to 8 hours without having to urinate.

But, persons with nocturia get up more than once during the night to urinate. Because of this, those who have excessive urination at night often have disrupted sleep cycles.

• Benign prostatic hyperplasia
• Certain drugs including diuretics, cardiac glycosides, demeclocycline, lithium, methoxyflurane, phenytoin, propoxyphene, and excessive vitamin D
• Chronic or recurrent urinary tract infection
• Chronic renal failure
• Congestive heart failure
• Cystitis
• Diabetes
• Drinking too much fluid before bedtime, particularly coffee, caffeinated beverages, or alcohol
• Obstructive sleep apnea and other sleeping disorders

Keep a diary of how much fluid you drink, how often you urinate, and urine output. Record your body weight at the same times and on the same scale daily.

Make an appointment with your doctor if:

• Excessive nighttime urination continues over several days, and is not explained by medications or increase of fluids before bedtime
• You are bothered by the number of times you must urinate during the night

Your health care provider will perform a physical examination and ask questions about your nighttime urination, such as:

• When did it start?
• How many times does this occur each night?
• Has there been a change in the volume of urine produced?
• Do you ever have "accidents" or bed wetting ?
• How much urine is voided each time?
• What makes the problem worse? Better?
• How much fluid do you drink before bedtime? Have you tried restricting fluids before bedtime?
• What other symptoms are also present? Do you have increased thirst , pain or burning on urination , fever , abdominal pain , or back pain?
• What medications are being taken?
• How much caffeine do you consume each day?
• Have you had any bladder infections in the past?
• Is there a family history of diabetes ?
• Does nighttime urination interfere with adequate sleep and rest?
• Do you drink alcoholic beverages and, if so, how much each day?
• Have you changed your diet recently?

Electrolytes and fluids will be monitored over a period of time.

Diagnostic tests that may be performed include:

• Blood urea nitrogen
• Serum creatinine or creatinine clearance
• Fluid deprivation
• Osmolality
• Serum electrolytes
• Urinalysis
• Urine concentration
• Urine culture

Treatment depends on the cause. If excessive nighttime urination is due to diuretic medications, you may be told to take your medication earlier in the day.

Asplund R. Nocturia, nocturnal polyuria, and sleep quality in the elderly. J Psychosom Res. 2004 May;56(5):517-25.