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': 'Side effect of phenytoin are all Except \nSelect and explain. \nA. Osteomalacia, B. Maculopapular rash, C. Sedation, D. Megaloblastic anaemia', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Side Effects. Headache, nausea, vomiting, constipation, dizziness, feeling of spinning, drowsiness, trouble sleeping, or nervousness may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly. Phenytoin may cause swelling and bleeding of the gums. Ref: KD Tripathi 8th ed.', 'role': 'assistant'}]