Why aren’t there any cough medicines that actually work?
© 2017 Roy Benaroch, MD
Coughing is one of the most common reasons parents bring their children to see me. And I can see why. Coughing is noisy and uncomfortable, and gets kids dirty looks in schools and subways. Even worse, coughing keeps kids and their parents awake. We’ve all been there, and no one likes to cough.
But: coughing is there, usually, for a reason. Almost all coughs are from upper respiratory infections (that’s fancy talk for common, ordinary colds caused by common, ordinary viruses.) People cough because viral infections cause excess mucus to form throughout your “respiratory tree” – from your nose, down your throat, down the airways deep into your lungs. And that mucus isn’t good. If it just sits there, that warm sticky mucus will attract bacteria like swimming pools attract children. Worse, once the bacteria are enjoying themselves in the sticky mucus, they’ll reproduce and make tons more bacteria, causing more inflammation and more sticky mucus.
Fortunately, we have a built-in, excellent way to get rid of that sticky mucus before it gets loaded with bacteria. It’s called “coughing”. Coughing brings the mucus up and out of the lungs and respiratory tract (it’s usually swallowed, which is harmless – respiratory bacteria cannot survive in your stomach.) Coughing also agitates the mucus, preventing bacteria from developing their defensive biofilm and creating a huge colony of pus-filled goo.
Coughing is good. It’s there for a reason. And: if we had a medicine that could genuinely stop a person from coughing, it would kill people. People taking that magic medicine would end up filled with infected mucus, and if they couldn’t cough it up, they’d die. There is no “medical” way to get out infected mucus. No medicine, no suction, no procedure we’ve ever come up with is nearly as effective as a good old fashioned, God-given cough.
There are dozens, maybe hundreds of medicines you can buy that allegedly help stop or reduce the cough. One brand of them has that adorable mucus-monster guy—which is ironic, because coughing is the only way to get rid of him. Why are there so many choices of cough and cold medications at the drug store? Because none of them work. Sure, some might make you sleepy, and a few might reduce nasal congestion for a little while. But none of them, zero, none, have ever been shown to reduce cough in any meaningful way.
How long should an ordinary cough last? Longer than you think. Only 50% of coughs with a common cold improve by day 10. Many last 2 or 3 weeks, and 1 in 10 children with ordinary coughs are still coughing well past that 3 week mark.
Not all coughing is medically benign. Many coughs are caused by asthma, which shrinks down the breathing tubes and causes them to collect even more mucus. Asthma-caused coughs need to be treated with asthma medicines (not with cough “suppressants” or any other alleged “cough medicines”.) Some coughs are triggered by post-nasal drip from allergies, and we do have effective strategies and medicines to treat those. Coughs can also be triggered by lots of other things, like a side effect of some medications, or by an inhaled foreign object, or by pneumonia (which in children is usually viral, but that’s another story for another day.) Though most coughing is ordinary and benign and viral, a bad or lasting or troublesome cough should be evaluated by a doctor to determine the cause.
So what to do with a child who’s coughing? Soothe the airway with extra liquids, maybe a popsicle or warm soup (either warmish or coolish liquids seem to help, whichever you or your child prefers.) Older kids can suck a cough drop. Some families swear by those vapor products, like Vicks, though evidence that they help is weak. Of all of the “medicines” that have ever been studied to help with cough in children, the one with the best-documented effectiveness is honey. Not honey-made-into-cough-medicine, just regular ordinary honey from the grocery store, which is safe to use from age 1 and up. Honey, of course, won’t stop the cough – nothing will, which is good – but it can be soothing and seems to help with the throat irritation.
Coughing has a purpose. It’s there to prevent an ordinary, mucousy cold from turning into something much worse. There’s no medicine that stops a cough, and that’s a good thing.
**Bonus! Didja know why it’s sometimes spelled mucus, and sometimes spelled mucous? Grammar can be fascinating and disgusting!