Abstract
Risperidone is an atypical antipsychotic agent widely used in the management of anger, aggression and behavioral problems in children and adolescents. Its use in children and adolescents is safe, and the most frequently reported side-effects are weight gain, listlessness and increased appetite. Enuresis continuum is a rare complication following risperidone use. This report describes two pediatric cases of enuresis continuum developing following risperidone use. The first case was a 9-year-old boy diagnosed with attention deficit hyperactivity disorder combined presentation and opposition defiant disorder. Diurnal and nocturnal enuresis began on the fifth day of 0.5 mg risperidone therapy and resolved four days after discontinuation of risperidone. The second patient was a 13-year-old boy diagnosed with Down syndrome, intellectual disability and conduct disorder. Diurnal and nocturnal enuresis commenced on the third day of 1 mg/day risperidone therapy and resolved 10 days after discontinuation of risperidone. Both patients were subsequently started on aripiprazole, with a low α-1 adrenergic blocking effect, and no enuresis occurred during follow-up.
Cases of both nocturnal and diurnal enuresis following risperidone use are rare in the previous literature. In addition to the central dopamine blocking caused by antipsychotics, mechanisms such as peripheral α-blockage involvement in relaxation of the urethral muscles and blocking of the pudendal muscleswith 5-HT2 and 5-HT3 antagonism have also been implicated in urinary incontinence. This report is important in terms of emphasizing the rare side-effect of both nocturnal and diurnal enuresis following risperidone use. Considering also the adverse impact of urinary incontinence of patients’ quality of life, it is important for clinicians to be aware of such a side-effect in order to increase compliance with treatment on the part of patients.

Key words: Antipsychotic, diurnal enuresis, nocturnal enuresis, risperidone, side effect