Combination therapy in the treatment of persistent nocturnal enuresis

To evaluate, in a retrospective study, the response rate of older children to combination therapy using a sustained-release anticholinergic agent, hyoscyamine, and a synthetic analogue of antidiuretic hormone, desmopressin acetate.

Twenty-eight patients (20 males and eight females, aged 9-18 years) diagnosed with nocturnal enuresis were evaluated using a questionnaire, history and physical examination. None had success with single-agent pharmacological therapy. All were begun on 0.375 mg of hyoscyamine and 20 microg of desmopressin intranasally at bedtime. The response rate was monitored at 2 and 4 weeks, and then every 3 months by recording dry nights on a calendar. To improve efficacy, the dosage of medication was adjusted up to 0.750 mg of hyoscyamine and 60 microg of desmopressin. Upon achieving dryness and spontaneous awakening to void, medication doses were tapered.

Within 6 months 16 (57%) patients were completely dry and six (21%) were dry at least 80% of nights. Nine patients relapsed during dose tapering and therapy was reinstituted. Presently, 17 (60%) patients are off medication (after a mean of 8 months of medication). Eight patients are still on medication and are dry at least 80% of nights. Combination therapy failed in three patients and they have transferred to a different regimen. None experienced untoward side-effects from the medications.

Most older children with nocturnal enuresis responded to combination therapy. These children require long-term follow-up and may need medication for up to 6 months because the relapse rate is fairly high. Combination therapy appears safe and reliable in treating nocturnal enuresis in older children who have had no success with other treatment modalities.