What's the medical term for having a runny nose after eating something spicy?
And the answer: Gustatory rhinitis.

The word gustatory relates to how something tastes, while the word rhinitis suggests an inflammation of the mucous membrane in the nose. Certain foods are known triggers, especially hot and spicy ones like hot peppers, garlic, salsa, and curry.
If you've ever enjoyed a delicious salsa or Thai curry, chances are you've experienced a few of the side-effects of a spicy dish. Watery eyes, hot tongues and, perhaps least appealing of all, runny noses are all part of your body's response to spicy stimuli. So, what gives?
Well, the reaction comes down to a few specific chemicals: capsaicin and allyl isothiocyanate. These chemicals are responsible for what scientists call a food's "pungency," or spiciness. Capsaicin is found in plants from the Capsicum genus, such as chili peppers, and is most concentrated in the tissue that holds the seeds. Allyl isothiocyanate is a colorless oil found in foods like mustard and wasabi.
These spicy chemicals aren't just accident of evolution, though. In the world of plants, capsaicin is a deterrent – it's concentrated around the seeds to keep seed-crunching mammals from destroying their chances to reproduce. So, when you chow down on something spicy, the food activates your pain receptors, not your taste buds. They then go on to create irritation in the mucous membranes that line your face, including (you guessed it) your sinuses. Once a spicy chemical inflames the membranes, they start producing extra mucus as a defense mechanism. Then, Achoo! Runny nose extravaganza.
