TherapyStudy findings
Cough (Cochrane review [seven studies])5; one RCT10
AntihistaminesTwo studies: no benefit
Antihistamine/decongestant combinationTwo studies: no benefit
Codeine plus guaifenesin (Robitussin AC)One study: no benefit
Dextromethorphan (Delsym)Two studies: no benefit
Dextromethorphan plus guaifenesin (Robitussin DM)One study: no benefit
Dextromethorphan plus salbutamol*One study: no benefit
Mucolytic (e.g., Letosteine*)One study: benefit
Other combinationsOne study: no benefit
Congestion and rhinorrhea (Cochrane reviews [four studies]6)
AntihistaminesTwo studies (one using astemizole): benefit
Antihistamine/decongestant combinationTwo studies: no benefit
DecongestantsNo studies