A Case of Priapism in a Child With Autism Spectrum Disorder, Possibly Due to Risperidone Treatment With Addition of Atomoxetine

In Brief Objectives Risperidone is an effective drug used for the treatment of irritability in children with autism spectrum disorder (ASD). Atomoxetine (ATX) is a well-tolerated drug used in first-line therapy in children with attention-deficit/hyperactivity disorder (ADHD). However, uncommon adverse effects of risperidone and ATX are a concern among mental health professionals. To our knowledge, this is the first case report of priapism after addition of ATX upon existing treatment with risperidone. Methods Written informed consent for publication was obtained from the patient and his parents, and their identities were concealed for ethical reasons. Results Here, we report a case of priapism as an adverse effect of ATX and risperidone treatment in a 7-year-old boy with ASD and comorbid ADHD. In this case, priapism was not observed with risperidone until ATX was added. Conclusions Priapism is a condition viewed as a medical emergency. Although risperidone-induced priapism is a rare phenomenon, it is advised for clinicians to consider the drug interactions in treatment of ASD and ADHD in terms of early diagnosis and intervention. The patient and his parents gave written consent for the use of patient information for publication.