This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Adrenergic System, Subject name: Pharmacology
[{'content': 'Oral and topical drug for nasal decongestion is - \nSelect and explain. \nA. Phenylephrine, B. Histamine, C. Methoxamine, D. Dopamine', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., Phenylephrine Phenytephrineo It is selective alpha 1 agonist.o Topically it is used as nasal decongestant and in eye for producing mydriasis when cycloplegia is not required,o It is also a part of oral nasal decongestant preparations.", 'role': 'assistant'}]