Is a runny nose contagious?

Not necessarily. A runny nose can be a symptom of something that can be passed from person to person, like the common cold or flu. But it could also have a non-contagious cause, like cold air exposure or hormones.

Why is only one side of my nose runny?

One side of your nose may be runny because of various reasons. You may have a deviated septum. In rare cases, you may have a spinal fluid leak. Another rare cause of a runny nose is nasal cavity or paranasal sinus cancer.

Is a constant runny nose serious?

A constant runny nose may not be serious. but talk to your doctor if it lasts more than 10 days. You should also talk to your doctor if you have a runny nose along with other symptoms such as a high fever.

Runny Nose: Symptoms, Common Causes, and Treatment

Does every season seem to be the season for a runny nose (rhinorrhea)? That's because there are 13 common causes of runny nose—some of which can affect you as equally at one time of year as any other.

The common cold and allergies may be obvious culprits, but there could also be something more surprising behind your sniffles (like spicy food or hormones).

This article discusses the 13 reasons you may have a runny nose and what you do to treat it so you can finally put the tissues away.

The Common Cold

Sick woman laying on sofa holding remote control. — Tom Merton / Getty Images

Also known as: Upper respiratory infection (URI)

The common cold can be caused by several viruses, rhinovirus being the most common.

The common caold causes a runny nose by allowing fluids to pass more easily through blood vessels in the nose. This allows for leakage of fluid or serum into the nasal passages. In other words. Sometimes you may have a runny nose on one side only or even a constant runny nose.

Rhinorrhea usually occurs within the first two to three days after you become infected with a common cold virus. Mucus usually starts out clear and may turn white, yellow, or even green after a couple of days.

Treating Runny Nose Due to a Cold

Treatments to help reduce a runny nose when you have the common cold include using intranasal ipratropium (Atrovent) or first-generation antihistamines (see below):

Brompheniramine (found in Dimetapp Cold & Allergy)
Chlorpheniramine (found in Chlor-Trimeton)
Dimenhydrinate (found in Dramamine)
Diphenhydramine (found in Benadryl Allergy)

If your runny nose continues for more than 10 days, see a healthcare provider. You may have a bacterial infection that can be treated with antibiotics.

Allergies

Woman blowing her nose at outdoor cafe — LeoPatrizi/iStock

Also known as: Hay fever and allergic rhinitis

Allergic rhinitis, also known as hay fever or allergies, can cause a runny nose. You may often experience a runny nose related to allergies during the spring or the fall.

You may get a runny nose because of your body's inflammatory response due to pollen in the air. Pollen comes from:

Flowering plants
Trees
Weeds
Grasses

Nasal secretions from allergies are usually clear, but they may also contain pus.

If you have mild to moderate symptoms related to allergies, the first line of treatment is an oral antihistamine or nasal antihistamine spray. Glucocorticoid nasal sprays are also effective.

Antihistamines will help with the runny nose. But antihistamines don't really work when trying to treat allergy-related nasal congestion.

Cold Air

Woman blowing nose outside. — Axel Bueckert / EyeEm / Getty Images

Have you gone outside to enjoy the fresh snow only to have a runny nose ruin the moment? If outside long enough, you might even develop chapped lips from constantly wiping your nasal secretions away from your upper lip.

Cold, dry air is known to dry out the nasal membranes. This changes the fluid balance in your nasal passages.

The change causes your inflammatory response and nasal nervous system reflexes to work together. As a result, you end up with a runny nose.

Eating Spicy Food

Hot peppers in a mason jar. — JBfotoblog / Getty Images

Also known as: Gustatory rhinitis

Scientists are still trying to figure out exactly why eating food can cause a runny nose.

What they do know is that it's not really an immune response. It's more likely related to stimulation of the nervous system. And it may be associated with a parasympathetic response, a response that is helpful in resting and digesting.

You are also more likely to experience this if you also have allergic rhinitis or a history of smoking.

While spicy foods like hot chili peppers anything seasoned with red cayenne are very likely to make your nose run if you have gustatory rhinitis, any food can cause this reaction if you have the condition.

You can reduce your symptoms of gustatory rhinitis when you avoid spicy foods. However a medicine such as intranasal atropine is also helpful when you can't avoid foods that are spicy. Surgery can be helpful too.

Hormones

Pregnant woman holding stomach. — Hero Images / Getty Images

Also known as: Hormonal rhinitis

Hormones can directly effect the membranes in your nasal passages, causing your mucous glands to become more reactive.

Levels of thyroid, growth, and female sex hormones all can play a role in hormonal rhinitis.

A runny nose and congestion are also common symptoms during pregnancy. Changes to blood vessels throughout the body can result in the pooling of blood in the nasal blood vessels.

The increased levels of a hormone called progesterone can also cause your blood vessels to not relax as normal. This also causes a runny nose. Symptoms related to rhinitis during pregnancy seem to mirror the levels of estrogen.

There is little information available on the treatment of hormonal rhinitis. Hormone replacement therapy does not seem to help treat symptoms.

If you are pregnant, you can try nasal saline spray or exercise to potentially help decrease symptoms. The following medications may also be considered for people who are pregnant or breastfeeding. But do not take them unless you have cleared it with your obstetrician or other healthcare provider:

Many other possible treatments may be considered harmful to your baby. Always ask your healthcare provider before starting a new medication.

Medications

Also known as: Medication-induced rhinitis

Runny nose is a known side effect of some medications. Each medication can cause runny nose in a different way.

While not a complete list, medications used to treat the following conditions are known to cause runny nose in some people:

Runny nose is also a possible side effect of birth control.

Exercise

Two women running. — Holde Schneider / Getty Images

Also known as: Vasomotor rhinitis

Aerobic exercise such as running, aerobics, and even intercourse may cause your runny nose. But if you experience a runny nose while being active outdoors, the cause may be more realistically related to;

Allergies
Cold weather
Another irritant

If you experience a runny nose frequently while being active, you can ask your healthcare provider if a medication called Atrovent (ipratropium) would be a good choice for you. It relaxes the muscles around your airways so you can breathe better.

Crying

Crying makes more tears than your body can drain. As a result, tears run over your cheeks. While crying, more tears flow through the lacrimal puncta into the nasolacrimal duct. This tube drains directly into your nose.

Crying naturally causes you to have a runny nose because of the way your tears drain from your eyes through the lacrimal puncta. The lacrimal puncta are small openings inside the eyelids. You are constantly generating tears to keep your eyes from drying out. These tears do not run down your cheeks like they do when you cry.

Chronic Sinusitis

Woman with sinusitis — Cecilie_Arcurs / Getty Images

The sinuses are four spaces or cavities located in your head. They are all connected through passageways. These sinuses are in charge of making mucus that drains from the nasal passageways into the nose. The mucus travels to the back of the throat so that you can swallow it.

As a result, the sinuses prevent bacteria and debris from being trapped inside your nose. When the sinuses get blocked, bacteria can grow and cause an infection.

If this occurs, you experience sinusitis. And if the sinusitis occurs for 12 weeks or more, it's called chronic sinusitis. One of the symptoms includes a runny nose. Other symptoms are:

Sinus drainage down the back of the throat
Facial pain
Facial pressure
Stuffy nose
Reduced sense of taste or smell

Not all sinus infections require medical treatment. They usually improve on their own. But some sinus infections require antibiotics. If you don't need an antibiotic, your doctor may recommend you treat it at home. These treatments include:

Using a saline nasal spray or decongestant nasal spray
Relieve nasal pressure by placing a warm moist cloth on your forehead or nose
Inhale steam from a warm shower or bowl of hot water

If you experience chronic sinusitis that does not respond to medication or at-home treatments, your doctor may recommend sinus surgery to treat the problem.

Sinus Polyps

Sinus or nasal polyps are soft growths of tissue inside your nose and sinuses. They make it difficult for you to breathe.

People who develop nasal polyps usually also have the following medical issues:

A runny nose is one of the symptoms of sinus polyps. But you may also experience:

Nasal congestion
Facial pressure
Facial pain
Loss of smell and taste
Headache
Sinus drainage

If your doctor determines you have sinus polyps, they will first try to treat them through medication. If medication doesn't get rid of the polyps, your doctor will suggest surgery.

Deviated Septum

The septum is the bone and cartilage that separates the nasal cavity into the right and left sides. When it leans to one side of the nasal cavity, it is called a deviated septum.

Deviated septums can cause breathing problems, including a runny nose. Other symptoms of a deviated septum are:

Stuffy nose
Difficulty breathing through either one or both nostrils
Repeated sinus infections
Noisy breathing in babies and children
Mouth-breathing while asleep in adults

Some people are born with a deviated septum. But you can also get a deviated septum because of an injury like a broken nose.

Most people don't need treatment for a deviated septum if their symptoms are mild. Some people with a deviated septum experience serious symptoms such as breathing problems or repeated sinus infections. In these cases, a doctor may recommend surgery called septoplasty. This type of surgery corrects the septum.

Spinal Fluid Leak

A special fluid surrounds your spinal cord and brain. This fluid is called the cerebrospinal fluid (CSF). A membrane surrounds the fluid. When there's a tear in the membrane, the fluid can leak out. This can occur because of a:

Head injury
Surgery
A medical procedure like a spinal tap

Sometimes, a spinal leak occurs for no particular reason.

Drainage from the ear and the nose are both rare symptoms that can occur. You may also develop a headache that gets worse when you sit but decreases when you lie down.

Spinal fluid leaks are a rare occurrence. If the doctor determines you have a spinal fluid leak, they will first recommend treatments such as bed rest for up to two weeks. Other treatments may include saline infusions, IV caffeine infusions, and hydration. If those treatments don't work, your doctor may recommend surgery.

Churg-Strauss Syndrome

Woman blowing her nose — dowell / Getty Images

Churg-Strauss syndrome, also known as eosinophilic granulomatosis with polyangiitis (EGPA), is a rare disease where cells inside your tissues or blood become inflamed or swell.

People who develop Churg-Strauss have a history of asthma or allergies. It's a rare disease. But it can affect your lungs, sinuses, and nose. It can also affect the following:

Heart
Kidneys
Skin
Intestinal tract
Joints
Nerves

In rare cases, Churg-Strauss Syndrome even affects the brain.

A runny nose is a common symptom of Churg-Strauss Syndrome. Other symptoms include:

If your doctor diagnoses you with Churg-Strauss Syndrome, they will most likely prescribe a steroid called prednisone if your symptoms are mild. This will reduce inflammation.

When prednisone doesn't help your condition, doctors may combine other medications with it. Some of these medications can only be used for a short period of time because of the risk of complications and side effects.

For example, they may also prescribe:

Methotrexate azathioprine
Mycophenolate mofetil
Cytotoxic agents such as cyclophosphamide
Mepolizumab

When to See a Doctor

A runny nose that isn't connected to a serious illness will usually go away on its own. But there are times you may need to see a doctor for a runny nose. You should visit your doctor if:

Your runny nose lasts more than 10 days
You have a high fever
You have a yellow or green discharge from your nose along with sinus pain or pressure
Your child has a runny nose on one side only and the fluid is bloody, green, or smells bad

Summary

If you have a runny nose, it may be caused by something as simple as the common cold. But that's not the only thing that can cause a runny nose. Allergies, cold air, exercise, crying, and spicy food can also make your nose run. But there are more serious causes too. If you experience a runny nose for more than ten days, you should contact your doctor. You should also contact your doctor if you experience severe symptoms that go along with your runny nose.

Frequently Asked Questions

Is a runny nose contagious?

Not necessarily. A runny nose can be a symptom of something that can be passed from person to person, like the common cold or flu. But it could also have a non-contagious cause, like cold air exposure or hormones.
Why is only one side of my nose runny?

One side of your nose may be runny because of various reasons. You may have a deviated septum. In rare cases, you may have a spinal fluid leak. Another rare cause of a runny nose is nasal cavity or paranasal sinus cancer.
Is a constant runny nose serious?

A constant runny nose may not be serious. but talk to your doctor if it lasts more than 10 days. You should also talk to your doctor if you have a runny nose along with other symptoms such as a high fever.