This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
[{'content': 'Drug having very narrow therapeutic range is- \nSelect and explain. \nA. Lithium, B. Seraline, C. Roboxetine, D. Dothiepin', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Lithium may also be used to treat alcoholism, schizoaffective disorders, and cluster headaches . Thus, lithium is an indispensable pharmaceutical component of modern psychiatric therapy. Unfounately, lithium also has a narrow therapeutic index, with therapeutic levels between 0.6 and 1.5 mEq/L Ref Davidson 23rd edition pg 1200', 'role': 'assistant'}]