Excessive need to get up and urinate that occurs several times during the night and is disruptive to sleep. This may lead to sleep fragmentation and excessive daytime sleepiness. There are many causes of nocturia, including drinking too much fluid right before bedtime. In older men, nocturia is most often related to urinary retention that occurs with benign prostatic hyperplasia (BPH). Medications, especially diuretics used to treat hypertension or swelling, also may cause frequent nighttime urination.