A 35-year-old man with intermittent explosive disorder (IED) has multiple episodes of verbal and physical aggression disproportionate to any provocation, causing relationship breakdown. Which pharmacological agent has the best evidence for reducing impulsive aggression in IED?

• A Lithium carbonate
• B Valproate
• C Fluoxetine (SSRI) ✓
• D Haloperidol

Explanation

SSRIs, particularly fluoxetine, have the strongest RCT evidence base for reducing impulsive aggression and irritability in IED. The mechanism involves serotonergic modulation of impulsive aggression circuits (orbitofrontal cortex and amygdala). Randomised trials by Coccaro et al. showed significant reduction in aggression scores with fluoxetine vs placebo. Mood stabilisers (lithium, valproate) have secondary evidence. Antipsychotics are used for acute agitation but are not first-line for IED long-term management. CBT (specifically anger management techniques) is the evidence-based psychotherapy.

Reference: Kaplan & Sadock's Synopsis of Psychiatry, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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