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: Forensic Medicine
[{'content': 'In which of the poisoning, gastric wash is contraindicated? \nSelect and explain. \nA. Oxalic acid, B. Sulphuric acid, C. Opiate, D. Dhatura', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Gastric lavage is useful any time within 3 hours after ingestion of a poison. The only absolute contraindication of gastric lavage is corrosive poisoning (except carbolic acid), owing to the danger of perforation. Precautions should be taken for convulsant poisons, in comatose patients, volatile poisons, upper alimentary diseases, marked hypothermia, and hemorrhagic diathesis. Ref: Essentials of Forensic Medicine and Toxicology by KS Narayan Reddy, 27th edition, Page 453.', 'role': 'assistant'}]