If you’re a normal human being you’ve probably had a few very bad colds in your lifetime. Maybe you’re trying to get through one right now. Sucking on a cough drop usually seems to produce a pleasant cooling sensation in your throat that alleviates the pain and opens up the nasal passages. But, what ingredient are in cough drops that give you that cooling sensation? The answer is menthol. Most cold remedies intended to soothe your throat and airways contain menthol. Now, how does menthol work? Why does menthol help you breathe?
First of all, let’s talk about where menthol comes from. Menthol comes from mint. It occurs naturally in peppermint oil, but more often than not the menthol products you consume were created in a laboratory. The demand for menthol far exceeds the amount of mint naturally occurring in nature, therefore it is much more efficient to create the menthol artificially.
When you suck on a cough drop and feel that cooling sensation, it’s due to the menthol reacting with receptors in your body that were designed to track the temperature of your environment. When the menthol reacts with these receptors, whatever is in contact with the menthol (your throat and nasal passageways) believes that the environment has rapidly cooled down. This reaction to the menthol stops muscle contractions in your lungs and reduces the sensitivity of your airways. This cooling reaction is the main reason why some cigarettes contain menthol. The menthol reduces the harshness of the cigarette smoke, and it allows you to breathe the smoke in without hacking up a lung.
The cooling sensation provided by low doses of menthol is actually reversed when a greater percentage of menthol is consumed. Try to put an entire bag of cough drops in your mouth. That soothing cool might just turn into a burning pain because higher concentrations of menthol tell those same temperature receptors that the environment is very hot.