A runny nose is mucus being discharged, or “running,” or dripping, out of the nose. It can be caused by colder outdoor temperatures, or by the cold, flu, or allergies.
When a cold virus or an allergen, such as pollen or dust, first enters the body, it irritates the lining of the nose and sinuses, or air-filled pockets around the face, and the nose starts to make a lot of clear mucus. This mucus traps the bacteria, virus, or allergens and helps flush them out of the nose and sinuses.
After 2 or 3 days, the mucus may change color and become white or yellow. Sometimes the mucus may also turn a greenish color. All of this is normal and does not mean an infection is present.
The breathing process starts in the nose. Air gets into the lungs through the nose. It helps filter, humidify, warm, or cool the air that comes through it, so that the air that gets to the lungs is clean.
A special lining of mucosa, or a moist tissue, covers the area inside the nose and consists of many mucus-producing glands. As bacteria, allergens, dust, or other harmful particles come into the nose, the mucus traps them. Mucus contains antibodies, or enzymes, which kill unwanted bacteria and viruses.
The mucosa lining also includes cilia, or tiny hair-like structures. The cilia are continually in motion and move the collected harmful particles and the mucus that they are trapped in through the nose into the back of the throat. It is then swallowed and destroyed by the acid in the stomach. Mucus and particles can also be coughed up or sneezed out.
When outdoor temperatures turn cold, the pace of this process slows down. Many times, the mucus stays in the nose and then drips or dribbles out of the nose.
Mucus production is a normal and necessary part of the airway system. Mucus is needed to keep the airway moist and working properly. Not only does mucus stop harmful particles from getting into the lungs, but it also contains antibodies to help destroy bacteria. If too much mucus is produced, the body wants to get rid of it, leading to coughing and spitting the extra mucus out, and blowing it out of the nose.
Postnasal drip is a side effect of too much mucus. It occurs when the mucus goes down the back of the throat and is swallowed, which may lead to a cough or sore throat.
Sometimes, a runny nose and a congested, or stuffy, nose are seen together. Congestion occurs when the tissues lining the nose become swollen and make it difficult to breathe. The swelling is due to inflamed blood vessels. Mucus may begin to run out of the nose.
A runny nose due to a cold or flu may be accompanied by fatigue, sore throat, cough, facial pressure, and sometimes fever.
A runny nose due to allergies may be accompanied by sneezing, and itchy, watery eyes.
Prescription medicine, such as antibiotics, is not needed to treat a runny nose, which usually gets better on its own. Sometimes, an over-the-counter decongestant medicine may help adults, but might not be appropriate if you have certain conditions or take other medications. Check with the doctor to see what over-the-counter medicines are appropriate for you.
Typically, the best treatment for a runny nose includes:
In addition, there are many safe and effective over-the-counter medications available to help control allergy symptoms, such as nasal steroid sprays and oral antihistamines. If the symptoms are severe, a doctor may recommend prescription medications, or referral to an allergist, for testing and targeted therapy.
Over-the-counter saline, or salt water, drops can be gently squirted into the nostrils to loosen the mucus in the nose. The liquid and mucus can then be suctioned out of the nose with a rubber syringe, or bulb.
Every person is different and over-the-counter medicines may relieve the symptoms of a runny nose for some and not others. The best treatment for a runny nose includes eating healthy, drinking plenty of fluids, and resting as much as possible.
Unless prescribed by the doctor, do not give over-the-counter cold medicines to a child under age 4 years.
Practicing good hygiene is important and often can help stop germs from spreading. Here are some simple tips:
A runny nose will typically go away on its own. However, a doctor should be called if:
The doctor will perform a physical examination to make sure the runny nose is not a symptom of a more serious condition.
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This information is provided by the Cleveland Clinic and is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition. This document was last reviewed on: 12/06/2017