<prompt> All of the following are anti tussives EXCEPT:CodeineDextromethorphanAmbroxolNoscapine  <response>: Ans. c AmbroxolRef. KDT 6th ed. 214 Ambroxol is a metabolite of bromhexine having mucolytic action. Antitussives are drugs that act in the CNS to raise the threshold of cough centre. Since antitussives aim to control rather than eliminate cough they are used only for dry unproductive cough or if cough is unduly tiring, disturbs sleep or is hazardous.MucolyticsAntitussives Bromhexine Ambroxol Acetylcysteine CarbocisteineOpioids Codeine PholcodeineNonopioids Noscapine Dextromethorphan Chlophedianol 