Over-the-counter cough syrup, that bizarrely flavored elixir that figures in nearly every… Over-the-counter cough syrup, that bizarrely flavored elixir that figures in nearly every American’s childhood, might be no better than a placebo.

The remedy, which is found in millions of medicine cabinets and is a billion-dollar industry, might not actually remedy anything.

The American College of Chest Physicians, which published a guideline for the treatment of coughs Monday, has cited studies showing that many non-drowsy OTC expectorants and suppressants do little at best to relieve cough symptoms. Research in 2004 indicated that dextromethorphan, often referred to as DM, and diphenhydramine, an antihistamine, offer no more relief than sugar water for treating children’s coughs caused by the common cold.

There are some drugs that have been proven to relieve cough symptoms. Codeine, a narcotic, and dextromethorphan, are both considered effective, but are only found in a few brands of cough syrup and not in high enough dosages for many doctors to consider them effective.

Some older antihistamines, like the diphenhydramine found in Benadryl or chlorpheniramine, are also proven substances – but they often make people drowsy and are not always marketed as treatment for cough.

What does this mean for those with bottles of something grape-flavored sitting in their bathroom closets? For many people, it means nothing worse than a possible waste of money.

Industry groups and manufacturers of cough syrups have pointed out the seemingly obvious: there are millions of people who feel like they are an effective treatment, so clearly, cough syrup must be doing something right.

For most of these people, the main lesson from this recent cough syrup controversy is not ‘don’t buy cough syrup,’ but ‘know what you are putting into your body.’

Not all cough syrups are created equal, and it’s worth taking the time to read the information on the box and understand the difference between how an antihistamine and how a decongestant work.

For some segments of the population, the ACCP indicates cough syrup may actually be harmful. It may keep people from seeking or delaying professional medical help for more serious conditions like whooping cough or pneumonia.

Children are easily overdosed on cough syrup, and unless their coughs are caused by chronic lung conditions of environmental factors, they will usually resolve themselves on their own.

What can be done, then, to relieve a cough? Doctors recommend patience and also drinking plenty of fluids. If one of those fluids is cough syrup, just be sure to read the label first.