This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Intravenous Anesthetic Agents, Subject name: Anaesthesia
Thiopentone in contraindicated in all except - 
Select and explain. 
A. Porphyria cuneata tarda, B. Staticus asthamaticus, C. Shock, D. Acute intermittent porphyria
A: Porphyria cuneata tarda
Answer: A: Porphyria cuneata tarda 
Explanation: Thiopentone is an barbiturate and being barbiturate it is enzyme inducers thus can precipitate porphyria But depending on enzyme affected it has been found to be safe in Porphyria cuneata tarda and absolutely contraindicated in Acute intermittent Porphyria. fuher being cardiovascular unstable it is contraindicated in shock. it is bronchoconstrictor so contraindicated in asthmatic patients .