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: Pharmacology
[{'content': 'Therapeutic drug monitoring is advised in allexcept \nSelect and explain. \nA. Metformin, B. Phenytoin, C. Tacrolimus, D. Cyclosporine', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Metformin o Drugs whose response is easily measurable eg. hypoglycaemics (metformin), antihypeensive, diuretics, oral anticoagulants and general anaesthetics, monitoring of plasma conc. is of no value.", 'role': 'assistant'}]