This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Respiratory system, Subject name: Pharmacology
[{'content': 'The following antitussive is present in opium but has no analgesic or addicting propeies \nSelect and explain. \nA. Codeine, B. Pholcodeine, C. Noscapine, D. Ethylmorphine', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Noscapine (Narcotine):- An opium alkaloid of the benzoisoquinoline series. Mech of action:- It depresses cough but has no narcotic, analgesic or dependence inducing propeies. It is nearly equipotent antitussive as codeine, especially useful in spasmodic cough. side effects:- Headache and nausea avoided r contraindication:- It release histamine and produce bronchoconstriction in asthmatics. Ref:- kd tripathi; pg num:- 220', 'role': 'assistant'}]