Which anaesthetic agent is contraindicated in porphyria

Ans. (c) Thiopentone Thiopentone sodium (a Barbiturate) Discovered by Water & Lundy 1934. It is ultra short acting barbiturates. Thiopentone is the drug is avoided in shock and hypotensive states. (AIIMS Nov 07) Contraindication Absolute - Porphyria thiopentone cause LMN paralysis in porphyria patients & even death. H/O thiopentone anaphylaxis. Relative - Hypotension Asthmatics Patient with fixed cardiovascular lesions who can't Cardiac output like tight valvular stenosis. Heart block, Constrictive pericarditis Inflammatory conditions of oral cavity and neck where airway maintenance is difficult Dystrophia myotonica Familial periodic paralysis Drugs that may precipitate porphyria a. Succinimides b. Carbamazepine c. Valproic acid d. Pyrazolones e. Griseofulvin f. Ergots g. Estrogens and progestogens h. Danazol i. Barbiturates (Phenobarbitone) j. Sulfonamide antibiotics k. Meprobamate l. Glutethimide m. Methyprylon n. Ethchlorvynol o. Mephenytoin p. Alcohol