RESUMEN
Background: This study intends to evaluate the relationship between medication switching and autistic traits, emotion dysregulation, and methylphenidate side effects in children with attention deficit hyperactivity disorder (ADHD). Methods: Children with ADHD, ages 9-18, treated with methylphenidate (MTP) (n = 23), and switched to atomoxetine (ATX) (n = 20) were included. All participants were interviewed with K-SADS-PL to confirm ADHD diagnosis and exclude comorbid psychiatric disorders. The participants then completed Difficulty in Emotion Regulation Scale (DERS) and Autism-Spectrum Quotient (AQ) and their parents completed Autism Spectrum Screening Questionnaire (ASSQ) and Barkley Stimulant Side Effect Rating Scale(BSSERS). Results: The MTP group scored higher than the ATX group in ASSQ, AQ, and the lack of emotional clarity subscale of DERS, while the ATX group had higher scores in the emotional non-acceptance subscale of DERS. No differences were found between the MTP and ATX groups in methylphenidate side-effect severity. Multiple regression analyses revealed that non-acceptance of emotions predicted the switch to ATX while lack of emotional clarity predicted the maintenance of MTP therapy, rather than autistic traits. Conclusions: This study highlights emotion regulation difficulties and how different emotional profiles may influence medication selection in children with ADHD.