This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anaesthesia
Thiopentone is contraindicated in 
Select and explain. 
A. Narcoanalysis, B. Neurosurgery, C. Acute intermittent porphyria, D. Induction of anaesthesia
C: Acute intermittent porphyria
Answer: C: Acute intermittent porphyria 
Explanation: Being an enzyme inducer (ALA synthetase)  thiopentone precipitates porphyria.