This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Autonomic nervous system, Subject name: Pharmacology
[{'content': 'Which of the following agent is not used in erectiledysfunction: \nSelect and explain. \nA. Apomorphine, B. Vardenafil, C. Phenylephrine, D. Alprostadil', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Ref; KD Tripathi pharmacology 7th edition page no;303 Drugs used in erectile dysfunction is Androgens : PDE-5 inhibitors; sildenafil, tadalafil, vardenafil PGE1; Alprostadil P papaverine Phentolamine -alpha blocker apomorphine- dopamine agonist Phenylephrine is an adrenergic drug which is contraindicated in erectile dysfunction', 'role': 'assistant'}]