This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Central Nervous system, Subject name: Pharmacology
[{'content': 'Drug having proven efficacy in bipolar depression is: \nSelect and explain. \nA. Carbamazepine, B. Valproate, C. Tiagabine, D. Lamotrigine', 'role': 'user'}, {'content': 'Answer: D \nExplanation: This newer anticonvulsant is now an approved drug for bipolar disorder, but is not recommended for acute mania. It is especially useful in rapidly cycling bipolar depression. Randomized trials have demonstrated its efficacy, both as monotherapy as well as adjuvant to lithium. It carrys minimal risk of inducing mania. The tolerability profile of lamotrigine is ourable. Ref: KD Tripati 8th ed.', 'role': 'assistant'}]