Enuresis - Medicine Treatments

Desmopressin is the medicine commonly used to treat bedwetting. It can be used for both short-term (for example, for a school trip or a sleep-over) and for long-term. It works in about 7 in 10 cases. This leaflet just discusses treating bedwetting (nocturnal enuresis) with medicines. Another separate leaflet called 'Bedwetting (Nocturnal Enuresis)' discusses bedwetting in more detail. There are also other separate leaflets called 'Bedwetting Alarms', discussing alarm treatments for bedwetting, and 'Bedwetting - Reward Systems', detailing reward systems to treat bedwetting.

What is desmopressin?

Desmopressin is the most popular medicine used to treat bedwetting. A dose is given just before bedtime. It comes both in tablet form which is swallowed, or as a melt tablet - that is, one you put under the tongue, which dissolves and goes straight into the bloodstream. The advantage of the melt form is that it is not affected by food in the stomach. (There used to be a nasal spray option. However, this is no longer prescribed for children due to an increase risk of side-effects compared with the tablet and melt preparations.)

How does desmopressin work?

Desmopressin works by reducing the amount of urine produced in the body at night by the kidneys. This means that the bladder then fills with less urine during the night-time.

Desmopressin is usually taken at bedtime. Your child should only have sips of fluid from one hour before taking desmopressin until eight hours afterwards (see below).

How effective is desmopressin?

Most children who take desmopressin will have an improvement. This may be fewer wet nights than usual rather than being totally dry every night.

Alternative medicines are sometimes used if desmopressin is not effective. These are usually prescribed by specialist doctors rather than by your GP.

What are the advantages of desmopressin?

Because of the way it works (reducing the amount of urine being made), it has an immediate effect on the first night of treatment. This can be very encouraging to the child.

If it has had no effect after a few days, it is unlikely to work at all. However, sometimes the initial dose is not high enough. A doctor may advise that the the dose be increased if it does not work at first. Also, it is possible that food can affect the absorption of desmopressin tablets into the body. Therefore, if it has not worked, then try giving the dose at least an hour and a half after the child last ate anything, and don't give food to your child just before bedtime. Alternatively, you could try the melt (under the tongue) preparation.

What are the disadvantages of desmopressin?

It does not work in all cases. Also, in children where it has worked, when it is stopped there is a chance that bedwetting will return. (A permanent cure following treatment is more likely with bedwetting alarms than with desmopressin.)

When and how is desmopressin used?

Treatment with a bedwetting alarm is currently recommended to be used as a first-line option. However, desmopressin is recommended first-line for children who require a rapid response or short-term control of bedwetting (for example, for sleep-overs or school trips) because it has a faster response rate than using an alarm. If it is used for short-term control then it usually recommended to take it around a week before the occasion it is needed for, in order to assess how effective it is.

Desmopressin is generally used only in children aged over seven years, but sometimes it is used in children a year or two younger. It is not used in children under the age of five years. Children aged 5-7 years may be given desmopressin if they are not yet considered to be mature enough to use a bedwetting alarm. It can also be used as an alternative to an alarm. Some children have desmopressin in addition to using the alarm.

If it works, it can be continued for a while. If there has been a response after four weeks then it is usually given for a total of three months and then stopped for a week to assess the effect to see if it is still needed. If there is only a partial response, the dose may be increased (and also be given one to two hours before bedtime) and then it should be continued for another six months. However, if there is no response after four weeks then the treatment is usually stopped. Sometimes it is recommended to try taking it one or two hours before bedtime to see if this works.

Desmopressin can also be useful for short spells. For example, it may be especially helpful for holidays or times away from home (sleep-overs, etc). It may also give encouragement to a child, who is fed up with bedwetting, to have a period of dry nights.

Are there any side-effects with desmopressin?

Side-effects are rare. Possible side-effects may include headache, feeling sick and mild tummy pain. These side-effects are not serious and go away if the treatment is stopped.

The most serious possible side-effect is due to the way the medicine works - it reduces the amount of urine that is made. Very rarely, this can lead to fluid overload (too much fluid in the body). This may lead to convulsions and serious problems. It has to be stressed that this is extremely rare and unlikely to happen. However, as a precaution, it is advised that when your child takes desmopressin:

  • He or she should not drink too much in the evening. Normal amounts to ease thirst are fine, but not extra drinks for pleasure, such as cans of lemonade.
  • He or she should not drink more than one regular cup of water (about 240 ml) from one hour before taking desmopressin to eight hours afterwards.

In effect, this means just give small drinks if your child is thirsty in the night.

Also, do not give desmopressin to a child who is ill with diarrhoea or vomiting until the illness has cleared. Children with vomiting and diarrhoea should be given plenty of fluids.

Further information and help

ERIC - Education and Resources for Improving Childhood Continence

34 Old School House, Britannia Road, Kingswood, Bristol, BS15 8DB
Tel (helpline): 0845 370 8008 Tel (admin): 0117 960 3060 Web: www.eric.org.uk Provides support and information (including booklets, CD-ROM, DVD, and video), and sells a range of products, including alarms, mattress and bedding covers, waterproof duvets, etc.