Why Do Chile Peppers Make People Cough?

In my house, we really like Mexican food. And Thai food. Oh, and Chinese food. We like all food, I guess, but that’s sort of beside the point. The point is that, because of our tastes, I wind up handling a lot of chile peppers (some people refer to hot peppers as chili peppers, but I prefer to use the Spanish spelling favored in Mexico and the American Southwest, so as not to confuse the peppers with that dish you often put them in). Sometimes these chiles are dried, or in the form of powders, pastes or oils. Often, though, they’re fresh, which means me cleaning and cutting them, which means me curling up in the fetal position on the kitchen floor coughing up a lung and crying like a little girl. Why does that happen?

Feel the Burn

The problem is that capsaicin, the compound that gives chiles their heat and livens up my fajitas and pad thai, doesn’t just work its tingly, burning magic on the tongue, but irritates also some of our other tissues and mucous membranes. Rubbing your eyes or scratching around your nostrils after handling chiles is always unpleasant, but you don’t need chile-to-skin contact to feel the burn. Washing, seeding, chopping and frying chiles can send capsaicin molecules flying into the air, where they can be inhaled and irritate and sensitize your lungs, leading to coughing fits, choking and discomfort while breathing.

Put Out the Fire

If cooking with chiles gets you all choked up, borrow this trick from pro cooks who work with them a lot: wear a damp bandana—or even a dish towel if you’re in a pinch—over your mouth and nose to cut down the amount of capsaicin that can make its way into your airways.

To get the stuff off your hands before you go touching your face, either wash with soap and water or rub some vegetable oil on your hands and then wash with water. Capsaicin is hydrophobic, so just water alone isn’t enough, but the soap and oil will both trap the molecules so they can be rinsed away.

Bonus Capsaicin Factoids for Your Next Cocktail Party

Capsaicin’s tendency to make people cough isn’t always a bad thing, and actually makes the compound pretty useful in medical research. In clinical studies of new cough suppressants, capsaicin is sometimes used to stimulate coughs for the medicine to be tested on.

The venom of Psalmopoeus cambridgei, a tarantula from the West Indies, contains three different peptides that target the same sensory receptors that respond to capsaicin, a really cool example of a plant and an animal using the same chemical methods for self-defense.

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