When I was a resident in training, researchers were actively trying to find a cause and cure for bedwetting. They thought that bedwetting was caused by having a small bladder and they thought that stretching the bladder would cure bedwetting. So they fed children diuretics that caused them to produce copious amounts of urine and asked them to sit in chairs and hold the urine. Needless to say the treatment didn't work, the children were miserable and today, more than 40 years later, a study from Denmark shows that bed wetting is not caused by having a small bladder. This confirms several studies showing that wetting the bed is usually caused by lack of antidiuretic hormone that is produced by the brain at night to shut down the kidneys and that this condition in young children can often be cured by taking a nasal spray or pill, called desmopressin, that shuts down the kidneys at night.

Desmopressin can also treat many men who urinate frequently at night, and do not have a prostate infection or cancer. Lack of antidiuretic hormone is genetic because fathers and mothers have children who also are bed wetters.

Bedwetting is common up to the age of eight, with most bed wetters growing up to become normal healthy adults. All children who wet the bed after age five should be evaluated by their pediatricians. They should have their urines checked for infection and perhaps a kidney x-ray to see if there is any abnormality in their urinary system. Most of the time, no cause is found. Bed wetters do not have more emotional or behavioral problems.

During the day, your kidneys are supposed to produce urine, but at night, your brain should produce an antidiuretic hormone called ADH, to shut down your kidneys. The brains of many bed wetters don't produce enough antidiuretic hormone at night, which causes their bladders to fill. When it happens to adults, they usually wake up and go to the bathroom, but bed wetters sleep through the night and wet the bed. For the last five years, doctors have treated bedwetting with a special nasal spray containing an antidiuretic hormone called desmopressin, but many children continue to wet their beds. Several studies show that taking a new 400 microgram desmopressin pill at bedtime and restricting fluids helps reduce bedwetting by almost 50 percent. Check with your doctor.