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: Unknown
[{'content': 'Tadalafil should not be given with: \nSelect and explain. \nA. Vasodilator, B. Antibiotics, C. Vasoconstrictors, D. Valproate', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Ref. KDT. Page. 190\nTALADAFIL:\n\nMore potent and longer acting congener of sildenafil\nt1⁄2 18 hours and duration of action 24–36 hours.\nActs faster\nSide effects, risks, contraindications and drug interactions are similar to sildenafil.\nBecause of its longer lasting action, nitrates are contraindicated for 36–48 hours after tadalafil. \xa0(vasodilators)', 'role': 'assistant'}]