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for older and highly motivated children is dry-bed training, which is an
intensive form of behavioural therapy that involves hourly waking on the
first night, high fluid intake and frequent behavioural rehearsal of proper
toileting. Though reportedly successful for some otherwise resistant cases,
the technique is not suitable for young and poorly motivated children,
who are likely to see it as a torture.
Bladder training
This involves regular fluid intake and toileting during the day, thereby in-
creasing the individual’s opportunities for learning normal bladder control.
Children and adolescents who experience urinary urgency are taught to go
to the toilet immediately if the sensation persists. There is some evidence
that this sort of daytime training can promote a switch from unstable to
stable bladder function at night.
Medication
The first choice should usually bedesmopressin (DDAVP), a synthetic
analogue of antidiuretic hormone that is probably best reserved for those
aged 7 or more (and is inappropriate for children under the age of 5). The
medication is generally very safe, though it is important to warn families of
the need to avoid large fluid intakes in the evenings in order to reduce the
small risk of water intoxication. Given before bedtime, desmopressin stops
bed-wetting in roughly 20% of users and reduces the frequency of bed-
wetting in many others. In many instances, though, relapse occurs as soon
as the medication is stopped. Despite this reversibility, desmopressin is still
a valuable symptomatic treatment that may enable a child or adolescent
to go on school trips or stay overnight with friends without having to
face the embarrassment of a wet bed. In addition, the combination of
desmopressin and an enuresis alarm may be more successful than an
alarm alone, resulting in a higher long-term cure rate. This is particularly
true for those with severe wetting or associated behavioural and family
problems.
Tricyclic antidepressantsin relatively low doses (for example, 25–75 mg
of imipramine at bedtime) have also been shown to perform better than
placebo in the symptomatic treatments for nocturnal enuresis. The effect
is evident within the first week, and does not seem to be due to the
antidepressant, anticholinergic or sleep-altering properties of tricyclics.
Tolerance may emerge after two to six weeks on medication, and immedi-
ate or delayed relapse on withdrawal of medication is very common. Since
tricyclics are no more effective than desmopressin but are considerably
more toxic in overdose, they should seldom be used nowadays.
Anticholinergic medicationssuch as oxybutynin may be of some use in
relaxing the bladder wall and increasing bladder capacity. There is weak
evidence that this may be helpful when the pattern of nocturnal enuresis
suggests bladder over-activity or instability (see above).