Reason for Runny Nose

What's in this article?

1 Runny Nose Overview
2 Reasons for Runny Nose
3 Causes of Runny Nose

Runny Nose Overview

Runny nose is excess drainage, which may range from a clear fluid to thick mucus, produced by the nasal and adjacent tissues and blood vessels in the nose. The drainage of runny nose may run out of your nose or down the back of your throat or both.

The terms “rhinorrhea” and “rhinitis” are often used interchangeably to refer to a runny nose. Strictly speaking, rhinorrhea refers to a thin, relatively clear nasal discharge. Rhinitis refers to inflammation of the nasal tissues from a number of causes, which usually results in a runny nose.

Nasal congestion may or may not accompany runny nose.

Reasons for Runny Nose

If your nose is running, there are several possible explanations:

You have a cold or the flu: When you have either one of these, your nose goes into mucus-making overdrive to keep the germ invaders out of your lungs and the rest of your body, where they might make you even sicker than you already are. You know what happens then: The mucus runs down your throat, out your nose, or into a tissue when you blow your nose. Or it can fill your sinuses, which is why you get that stuffy feeling.

You have allergies: Kids who have allergies get runny noses when they’re around the thing they’re allergic to (like pollen or animal hair). That’s because their bodies react to these things like they’re germs.

You’re crying: When you cry, tears come out of the tear glands under your eyelids and drain through the tear ducts that empty into your nose. Tears mix with mucus there and your nose runs.

Baby, it’s cold outside: When you’re outside on a cold day, your nose tries its best to warm up the cold air you breathe before sending it to the lungs. Tiny blood vessels inside your nostrils open wider (dilate), helping to warm up that air. But that extra blood flow leads to more mucus production. You know what happens next. Drip, drip, drip.

Causes of Runny Nose

Runny nose can be caused by anything that irritates or inflames the nasal tissues. Infections such as the common cold and influenza allergies and various irritants may all cause a runny nose. Some people have a chronically runny nose for no apparent reason a condition called nonallergic rhinitis or vasomotor rhinitis (VMR).

Less commonly, runny nose can be caused by polyps, a foreign body, a tumor or migraine-like headaches.

Causes of runny nose include: