Snot, or nasal mucus, is a helpful bodily product. The color of your snot can even be useful for diagnosing certain illnesses.

Your nose and throat are lined with glands that produce 1 to 2 quarts of mucus every day. You swallow that mucus all day long without knowing it.

The main job of nasal mucus is to:

  • keep the linings of your nose and sinuses moist
  • trap dust and other particles you inhale
  • fight infections

Mucus also helps moisten the air you inhale, which makes it easier to breathe.

Normally, mucus is very thin and watery. When the mucous membranes become inflamed, however, mucus can thicken. Then it becomes the runny-nose snot that is such a nuisance.

Several conditions can cause nasal membrane inflammation. They include:

Mucus is usually clear and watery. If you have a bacterial infection, the color can change to green or yellow. This color change isn’t absolute proof of a bacterial infection, however. It can be a sign that a bacterial infection has developed on the heels of your viral infection, but a doctor’s evaluation is still needed to confirm the nature of your illness.

Increased snot production is one way your body responds to colds and allergies. That’s because mucus can act as both a defense against infection and a means of ridding the body of what is causing inflammation in the first place.

When you have a cold, your nose and sinuses are more vulnerable to a bacterial infection. A cold virus can trigger the body to release histamine, a chemical that inflames your nasal membranes and causes them to produce a lot of mucus. How is that a defense?

Thicker mucus can make it more difficult for bacteria to settle on the linings of your nose. A runny nose is also your body’s way of moving bacteria and other unneeded materials out of your nose and sinuses.

Allergic reactions to dust, pollen, mold, animal hair, or any of hundreds of allergens can also cause your nasal membranes to become inflamed and produce excessive mucus. The same is true of nonallergenic irritants that enter your nose or sinuses.

For example, breathing in tobacco smoke or getting water up your nose when swimming can trigger a short-term runny nose. Eating something very spicy can also cause some temporary inflammation of your nasal membranes and the production of harmless but excess snot.

Vasomotor rhinitis

Some people seem to have a runny nose all the time. If that’s the case for you, you may have a condition called vasomotor rhinitis. “Vasomotor” refers to nerves that control blood vessels. “Rhinitis” is an inflammation of the nasal membranes. Vasomotor rhinitis can be triggered by:

  • allergies
  • infections
  • prolonged exposure to irritants in the air
  • stress
  • other health problems

Vasomotor rhinitis causes the nerves to signal the blood vessels in the nasal membranes to swell, prompting more mucous production.

One trigger for a runny nose that has nothing to do with infections or allergies, or any other medical condition, is crying.

When you cry, the tear glands under your eyelids produce tears. Some roll down your cheeks, but some drain into the tear ducts at the inner corners of your eyes. Through the tear ducts, tears empty into your nose. They then mix with mucus that lines the inside of your nose and produce clear, but unmistakable, snot.

When there are no more tears, there’s no more runny nose.

Getting rid of snot means treating the underlying cause of your runny nose. A cold virus usually takes a few days to run its course. If you have a runny nose that lasts for at least 10 days, even if the snot is clear, see a doctor.

Allergies are often a temporary problem, like a pollen bloom that keeps the allergens in the air for several days. If you know the source of your snot is an allergy, an over-the-counter antihistamine may be enough to dry out your nose. Antihistamines may cause side effects in some people, such as:

If you have questions or you’re unsure how an antihistamine might interact with other medications you take, talk with your doctor or a pharmacist.

Prescription and over-the-counter decongestants may help you get through a cold. However, these drugs can have an effect in the body similar to that of a shot of adrenaline. They can make you jittery and cause a loss of appetite. Read the ingredient list and the warnings before taking any medication, including a decongestant.

Do you want to learn more about relieving a stuffy nose? Here are eight things you can do now to clear up your congestion.

If you have excess nasal congestion from a cold or allergies, over-the-counter medications and a little patience should help treat the symptom.

If you find yourself reaching for a tissue, remember to blow your nose gently. Vigorous nose blowing can actually send some of your mucus back into your sinuses. And if there’s bacteria in there, you may be prolonging your congestion problem.