Medically reviewed on January 11, 2018.
Runny nose is excess drainage produced by nasal and adjacent tissues and blood vessels in the nose. This drainage may range from a clear fluid to thick mucus. Runny nose drainage may run out of your nose, down the back of your throat or both.
The terms "rhinorrhea" and "rhinitis" are often used to refer to a runny nose. Strictly speaking though, 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.
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:
- Acute sinusitis (sinus infection)
- Chronic sinusitis
- Churg-Strauss syndrome
- Common cold
- Decongestant nasal spray overuse
- Deviated septum
- Drug addiction (substance use disorder)
- Dry air
- Granulomatosis with polyangiitis (Wegener's)
- Hormonal changes
- Influenza (flu)
- Lodged object
- Nasal polyps
- Nonallergic rhinitis (chronic congestion or sneezing not related to allergies)
- Occupational asthma
- Respiratory syncytial virus (RSV)
- Spinal fluid leak
- Tobacco smoke
When to see a doctor
A runny nose may be annoying and uncomfortable, but it usually clears up on its own. Occasionally, it can be a sign of a more serious problem, and runny nose may be serious in infants.
Call your doctor if:
- Your symptoms last more than 10 days.
- You have a high fever.
- Your nasal discharge is yellow and green and is accompanied by sinus pain or fever. This may be a sign of a bacterial infection.
- You have blood in your nasal discharge or a persistent clear discharge after a head injury.
Call your child's doctor if:
- Your child is younger than 2 months and is running a fever.
- Your baby's runny nose or congestion causes trouble nursing or makes breathing difficult.
Until you see your doctor, try these simple steps to relieve symptoms:
- Sniffing and swallowing or gently blowing your nose.
- Avoid known allergic triggers.
- If the runny nose is a persistent, watery discharge, particularly if accompanied by sneezing and itchy or watery eyes, your symptoms may be allergy-related and an over-the-counter antihistamine may help. Be sure to follow the label instructions exactly.
- For babies and small children, use a soft rubber suction bulb to gently remove any secretions.
Try these measures to relieve postnasal drip — when excess mucus accumulates in the back of your throat:
- Avoid common irritants such as cigarette smoke and sudden humidity changes.
- Drink plenty of water.
- Try nasal saline sprays or rinses.