All of the following are true about antitussives, except
Carbocistene contains blocked sulphydryl group.
Dextromethorphan is a NMDA blocker which acts as central antitussive
Ambroxol is a mucolytic that causes depolymerisation of mucopolysaccharides
Carbocistene is a mucolytic with free sulphydryl group
Baclofen is a peripheral acting antitussive