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: Pathology
[{'content': 'Which of the following drugs is not effective in case of Trigeminat Neuralgia? \nSelect and explain. \nA. Carbamazipine, B. acetaminophen, C. Phenytoin sodium, D. Baclofen', 'role': 'user'}, {'content': 'Answer: B \nExplanation: None', 'role': 'assistant'}]