dextrotomorphan, is the cough medicine, i find it has little effect on coughs. i believes its the 1st generations(diphenhydramine, doxylamine,bropheneramine,etc) anti-histamine that is preventing the smptoms, because also prevents mucus production via anti-cholingernic effects and the cough, besides the fever.

and pehnyleprine has no effect on you what so ever, you need the pseudoephedrine, but its regulated in the usa, and only available at the pharmacy counter, because Pseudoephedrine is used to make METH. dextromorphan is also recently been regulated, requiring ID, because stupid young children teens, are robotripping on it apparently.