At the first sign of foreign invaders, coughing acts as a primary line of defense, expelling whatever virus or bacteria is trying to make its way into the system. During this time it’s especially helpful when coughing to cover your mouth, with your inner elbow if possible, to prevent the spread of illness.

However, there may be other reasons for a cough that hangs on after a cold has run its course. To understand this we need to take a deeper look at the inner workings of the respiratory system.

The respiratory tract is lined from nose to lungs with a thin layer of mucous, a primary function of which is to trap particles, from smoke to mold to viruses. This mucous is perpetually propelled upwards through the throat by small hairs called cilia. Eventually the mucous is unconsciously swallowed, and particles are destroyed by the acidic environment within the stomach.

The issue arises when an infection damages cilia. It’s capable of growing back, but it may take 4-6 weeks for cilia to recover fully. Thus mucous builds up but isn’t able to move as freely as it normally does. In this case the body’s next best option is to use coughing as a mechanism to propel mucous outward. And so while it may be the case that a cold has already passed, the body works tirelessly to keep defense mechanisms up to prevent another infection from occurring.

Often if the body needs to cough it’s simply doing its job to keep any danger at bay, and therefore is a positive thing. One exception is when coughing is so relentless that it keeps us from sleeping. The body does much if its work to repair, rebuild and reconstruct during sleep. Therefore if coughing is interfering with rest, it may be prudent to utilize some form of cough suppressant specifically at bedtime. Some natural, and perhaps surprising, options include honey and dark chocolate. To read more about a prescription for dark chocolate, read here.

Subscribe for DrGreene’s Newsletter

Alan Greene MD contributor

Read more on: Contagious