The Effect of Clonazepam on Sleep Terror and Co-Occuring Nocturnal Enuresis in an Adolescent

To the Editor:

Sleep terror is a parasomnia characterized by a sudden arousal accompanied by a scream or cry that arises out of slow wave sleep. Typically, the person returns to sleep and cannot remember what he or she experienced during the night. The etiopathogenesis of the disorder is not clear, and behavioral treatments including psychoeducation, safety measures, and sleep hygiene are suggested first-line treatment. In addition, there are several case reports about the efficacy of imipramine and clonazepam on sleep terror (Remulla and Guilleminault 2004; Wichniak et al. 2012).

Although data regarding the association between enuresis and sleep have been somewhat contradictory, nocturnal enuresis is classified as a parasomnia according to the International Classification of Sleep Disorders. Children with nocturnal enuresis have longer time in bad and increased number of sleep cycles, are heavy sleepers, and enuresis occurs in non-rapid eye movement (NREM) stage of sleep. There are some reports about the possible links between nocturnal enuresis and other parasomnias (Mason and Pack 2007). However, the underlying mechanism of these relationships and their treatment are not known. Herein, we present an adolescent with sleep terror and co-occurring nocturnal enuresis who displayed complete remission after clonazepam therapy.

Case Report

A 15-year-old boy was referred to the outpatient clinic with complaints of awakening in the middle of the night, screaming, not responding to commands, throwing and damaging objects in the bedroom, and having difficulty about calming down. These symptoms were present since he was 2 years old, which gradually increased in recent years. The patient also had bed wetting from his childhood approximately three to four times per week. No other past or existing history was important. His physical and neurological examination was normal. The patient was diagnosed as having sleep terrors and primary nocturnal enuresis according to The Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-5) diagnostic criteria. Because of the symptom severity and chronicity, medical treatment was started immediately in addition to the behavioral suggestions. Clonazepam treatment was commenced at 1 mg/day, resulting in complete resolution of both sleep terrors and enuresis after the first day of the treatment. This boy revealed no signs of sleep terror or enuresis over the follow-up period of 5 weeks.

Discussion

Enuresis and sleep terror occur in the NREM phase of sleep and it is known that benzodiazepines like clonazepam inhibit stages N3 and N4, which are known as slow-wave sleep of the NREM sleep. Benzodiazepines also would stabilize sleep by decreasing transitions from N3 sleep into N2, and N1 sleep, and decrease stage shifts (Kotagal 2012). Furthermore, imipramine, which has an inhibiting effect on NREM sleep phase, is also used to treat both disorders (Wichniak et al. 2012). Therefore, clonazepam might treat these disorders and affect NREM phase of sleep in our patient. Although we cannot exclude the placebo effect, to the best of our knowledge, this is the first report suggesting that clonazepam may be effective for both sleep terrors and nocturnal enuresis. Further research is needed to explain these effects of clonazepam.