Adults who wet the bed at night often have problems in the daytime as well, such as having to rush to the lavatory (urgency). It may be caused by a mixture of reasons. If you have always suffered from bed-wetting, you may:

• lack the necessary muscle and nerve control
• produce a lot of urine at night
• suffer from chronic constipation
• (rarely) have an underlying congenital malformation of the urinary tract

If you have only recently started to wet the bed, it could be caused by:

• a urinary tract infection (UTI)
• alcohol, coffee
• diuretic medicines
• diabetes
• stress or anxiety
• constipation
• an enlarged prostate (in older men)

Lack of necessary muscle and nerve control. Your bladder may not yet have developed the necessary nerve and muscle control, so the bladder muscle contracts and empties the bladder when it is only half full of urine. If you are a teenager, your bladder should soon learn.

Producing a lot of urine at night. You may be producing a lot of urine, because the mechanisms that reduce urine production at night may not be working properly. Again, if you are a teenager, the problem may resolve itself in time.

Urine infection. A urine infection can irritate the bladder, and make it more difficult to hold urine.

Alcohol, coffee or diuretic medicines. Diuretics are medications that are used to treat high blood pressure and some heart problems. They encourage the kidney to make more urine. It is best not to take a diuretic at bedtime, because you will need to pass urine in the night and, if your bladder control is poor, this could cause bed-wetting. Alcohol and coffee have a similar effect, so avoid them within 3 hours of bedtime.

Diabetes mellitus is a disease in which the blood sugar is too high. The kidneys try to lower blood sugar levels by making lots of sugary urine, so you pass more urine and become more thirsty. If your bladder control is poor, this could cause bed-wetting. The problem goes away when the diabetes is properly treated.

Stress and anxiety can cause bed-wetting.

Constipation can increase pressure on the bladder and also affect the way the nerves controlling the bladder valves work.

An enlarged prostate which occurs naturally as men get older.

First published on embarrassingproblems.com
Reviewed and edited by Dr Kevin Barrett
Last updated: May 2025 by Dr Kevin Barrett