Description:
Introduction: Attention deficit hyperactivity disorder (ADHD) is a common disease inchildhood and adolescence. In about 60% of pediatric patients, the symptoms persistinto adulthood. Treatment guidelines for adult ADHD patients suggestmultimodal therapyconsisting of psychostimulants and psychotherapy.Many adult ADHD patients also sufferfrompsychiatric comorbidities, among others obsessive–compulsive disorder (OCD). Thetreatment of the comorbidity of ADHD and OCD remains challenging as the literature issparse. Moreover, the impact of psychostimulants on obsessive–compulsive symptomsis still unclear.Case Presentation: Here, we report on a 33-year-old patient with an OCD who wasunable to achieve sufficient remission under long-term guideline-based treatment forOCD. The re-examination of the psychological symptoms revealed the presence of adultADHD as a comorbid disorder. The patient has already been treated with paroxetine andquetiapine for the OCD. Due to the newly established diagnosis of ADHD, extendedreleasemethylphenidate (ER MPH) was administered in addition to a serotonin reuptakeinhibitor. After a dose of 30mg ER MPH, the patient reported an improvement in both theADHD and the obsessive–compulsive symptoms. After discharge, the patient reducedER MPH without consultation with a physician due to subjectively described side effects.The discontinuation of medication led to a renewed increase in ADHD and obsessive–compulsive symptoms. The readjustment to ER MPH in combination with sertraline andquetiapine thereafter led to a significant improvement in the compulsive symptoms again.Conclusion: The present case shows that in ADHD and comorbidobsessive–compulsive disorder, treatment with psychostimulants can improve theobsessive–compulsive symptoms in addition to the ADHD-specific symptoms. To ourknowledge, this is only the second case report describing a treatment with ER MPHfor an adult patient with OCD and ADHD comorbidity in the literature. Further research,especially randomized controlled trials, is needed to standardize treatment options.