Coughing is one of the germ’s mechanisms for spreading itself to a non-infected victim. Same with sneezing and projectile vomiting, and even diarrhea. Once the illness is finished, oftentimes people continue to cough as there may be a buildup of phlegm and dead germ cells in the lungs or throat. Does cough medicine work? Well, the first thing to consider here is the placebo effect. If people believe a medicine will work, oftentimes it will work even if the medicine is simply sugar pills. The brain is a very powerful organ, and we have a far ways to go before we can understand it completely. So the mere fact that you are taking medicine to help with your cough may make your cough subside, if you believe in it. Theoretically you could believe that a cup of orange juice could do the same, and it might work, although it’s less likely to because it’s obvious that orange juice is not a medicine. Scientifically, I don’t believe cough medicine works beyond the placebo effect, and there has been research done that supports this finding.