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Methylphenidate in ASD-ADHD — MRCPsych Paper B MCQ

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ModerateChild & Adolescent PsychiatryMethylphenidate in ASD-ADHDMRCPsych Paper B

A 7-year-old boy with ADHD and autism spectrum disorder started methylphenidate 2 weeks ago. His ADHD symptoms began to improve, but 4 days ago the dose was increased. Since then, he has developed persistent irritability and social withdrawal that were not previously present. There are no psychotic or manic symptoms and no immediate safety concerns. According to NICE NG87, what is the most appropriate next step?

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Correct answer: B — Reduce the methylphenidate dose, reassess, and use slower titration with more frequent monitoring

Explanation lettering: E = shown as A · A = shown as C · C = shown as D · D = shown as E

B is correct. The close temporal relationship between the dose increase and new irritability and social withdrawal, together with benefit at the lower dose, suggests methylphenidate-related behavioural adverse effects. NICE advises titrating ADHD medication against both benefit and adverse effects until effects are tolerable. Titration should be slower and monitoring more frequent when autism spectrum disorder is present; worsening behaviour should prompt medication adjustment and diagnostic review. Returning to the previously tolerated dose and reassessing is therefore appropriate. Continuing unchanged for 3 months would delay management of significant adverse effects. Risperidone is not a substitute for addressing a stimulant-related reaction. Adding fluoxetine would not treat the likely cause and could add adverse effects. Increasing methylphenidate would risk worsening the symptoms. Persistent intolerance may subsequently require stopping or changing ADHD medication.

Reference: National Institute for Health and Care Excellence. Attention deficit hyperactivity disorder: diagnosis and management (NG87), recommendations 1.7.26–1.7.28, 1.8.18 and 1.10.3. 2018, last updated 2019. https://www.nice.org.uk/guidance/ng87/chapter/recommendations