Excessive urination at night is a condition in which you wake up several times during the night to urinate. Waking up at night to urinate is called nocturia.

Nocturia

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

People who have nocturia get up during the night to urinate. Because of this, they often have disrupted sleep cycles.

• Benign prostatic hyperplasia
• Chronic or repeated urinary tract infections
• Drinking alcohol, caffeinated beverages, or too much fluid before bedtime
• Chronic renal failure
• Congestive heart failure
• Cystitis
• Diabetes
• High blood calcium level
• Medications including diuretics, demeclocycline, lithium, methoxyflurane, phenytoin, and propoxyphene
• Obstructive sleep apnea and other sleeping disorders

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

Make an appointment with your health care provider 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 amount of urine you produce?
• Do you ever have "accidents" or bed-wetting?
• How much urine do you release at a time?
• What makes the problem worse? Better?
• How much fluid do you drink before bedtime? Have you tried limiting fluids before bedtime?
• What other symptoms do you have? Do you have increased thirst, pain or burning on urination, fever, abdominal pain, or back pain?
• What medications are you taking?
• How much caffeine do you consume each day?
• Have you had any bladder infections in the past?
• Do you have a family history of diabetes?
• Does nighttime urination interfere with your sleep?
• Do you drink alcoholic beverages? If so, how much each day?
• Have you changed your diet recently?

Tests that may be performed include:

• Blood sugar (glucose)
• Blood urea nitrogen
• Fluid deprivation
• Osmolality, blood
• Serum creatinine or creatinine clearance
• 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.

Gerber GS, Brendler CB. Evaluation of the urologic patient: History, physical examination, and the urinalysis. In: Wein AJ, ed. Campbell-Walsh Urology. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 3.

Landry DW, Bazari H. Approach to the patient with renal disease. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 116.