Also called nocturia, frequent urination at night or while you're sleeping is relatively common. But, what causes it? Frequent urination and the urgency to urinate often can be the result of simple issues, like drinking too much before bed, to more serious problems, like disease.

Drinking Too Much

One of the most common causes of frequent urination at night or while you're sleeping is drinking too much before bed. Caffeinated drinks and alcohol, especially, can lead to a frequent need to urinate at night.

Enlarged Prostate

In men, an enlarged prostate, pushing against the bladder, can be the cause of a frequent need to urinate at night or while sleeping. In severe cases, an enlarged prostate can even result in bed wetting.

Urinary Tract Infection

If you're waking up to rush to the bathroom a lot every night, you may have a urinary tract infection. Check for abdominal pain, fever and pain or a burning sensation during urination. These are also symptoms of a urinary tract infection.

Medications

Some medications act as diuretics and cause frequent urination throughout the day, including at night. If you've recently started to have difficulty with frequent urination at night and just began taking a new prescription, check with your doctor.

Other Causes

Other causes of frequent urination include: pregnancy, overactive bladder syndrome, diabetes, bladder problems, kidney problems, prostate cancer, radiation therapy, neurological diseases and stroke.

Source:

Wrong Diagnosis:Causes of Night Urination

WebMD: Frequent Urination in Men and Women

Medline Plus: Frequent or Urgent Urination