A 7-year-old boy is brought to the paediatric psychiatry clinic by his mother with complaints of inattention and hyperactivity for the past 2 years. The teacher reports that he frequently leaves his seat during class, interrupts others, and struggles to complete assignments. At home, he is restless, talks excessively, and has difficulty waiting his turn during games. His mother reports he was born at term with no perinatal complications. On examination, he is alert and oriented but fidgety. Cognitive testing shows average intelligence. The child meets DSM-5 criteria for ADHD, combined presentation. His parents ask about pharmacological management. Which of the following is the first-line pharmacological agent for ADHD in children?

Explanation

## First-Line Pharmacotherapy for ADHD in Children **Key Point:** Methylphenidate (a psychostimulant) is the first-line pharmacological agent for ADHD in children across most international guidelines, including DSM-5 and Indian psychiatric practice standards. ### Mechanism of Action Methylphenidate is a selective norepinephrine and dopamine reuptake inhibitor that enhances catecholaminergic neurotransmission in the prefrontal cortex and striatum, improving attention, impulse control, and executive function. ### Efficacy & Evidence - **Onset:** Rapid (30–60 minutes for immediate-release formulation) - **Efficacy rate:** 70–80% response in children with ADHD - **Duration:** Immediate-release: 3–5 hours; extended-release: 8–12 hours - **Cost-effectiveness:** Widely available and affordable in India ### Dosing in Children - **Starting dose:** 5 mg once or twice daily - **Titration:** Increase by 5–10 mg weekly based on response and tolerability - **Maximum:** 60 mg/day (or 2 mg/kg/day, whichever is lower) ### Monitoring Parameters - **Baseline:** Height, weight, blood pressure, heart rate, ECG (if cardiac risk factors) - **During treatment:** Growth, appetite, sleep, mood, cardiac parameters at each visit ### Common Side Effects - Appetite suppression, insomnia, headache, abdominal discomfort - Usually mild and transient; dose reduction often helps **High-Yield:** Psychostimulants (methylphenidate, amphetamines) are preferred over non-stimulants because they have faster onset, superior efficacy, and decades of safety data in paediatric populations. ### Contraindications to Stimulants - Untreated hypertension - Cardiac arrhythmias or structural heart disease - Active substance use disorder (in adolescents) - Severe anxiety or psychosis (relative) **Clinical Pearl:** Always obtain baseline vital signs and ECG in children with a family history of sudden cardiac death or personal cardiac symptoms before starting stimulants.