In which of the following disorders,administration of barbiturates is contraindicated?: (A) Anxiety disorders, (B) Acute intermittent porphyria, (C) Kernicterus, (D) Refractory status epilepticus
Answer is B. Barbiturates induce the rate limiting enzyme amino levulanic acid synthase in porphyrin synthesis. This increased synthesis of prophyrins can precipitate acute attack of AIP Ref: KD Tripathi 8th ed.