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': 'Most common side effect of DH Ps calcium channe blockers is - \nSelect and explain. \nA. Headache, B. Constipation, C. Diarrhoea, D. Muscle cramps', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ans. is `a\' i.e., Headache o The most common side effects caused by the Ca" channel antagonists, paicularly the dihydropyridines, are due to excessive vasodilator. Symptoms include dizziness, hypotension, headache, flushing, digital dysesthesia, and nausea.', 'role': 'assistant'}]