Why does nose run?

Quick Dose: Why Does the Cold Weather Make My Nose Run?

Chilly air means sniffly noses. When we breathe in, our noses warm the air and add moisture to it as it travels down into our lungs. Cold, dry air irritates your nasal lining, and as a result, your nasal glands produce excess mucus to keep the lining moist. That can cause those big, heavy drops that drip from your nostrils. Wearing a scarf in cold weather can help, because the air warms before it hits your nose.

A runny nose is one of the most typical symptoms of the common cold. We are more likely to pick up a cold in the winter because we spend more time inside, and germs are able to survive longer in dry air. We’re exposed to millions of germs every day that linger on doorknobs, keyboards and phones.

Frequent handwashing, cleaning surfaces at home and work, sneezing or coughing into your elbow, and staying home when you’re sick are key to avoid picking up — and spreading — germs.

If a runny nose is bothersome, ask your physician about some over-the-counter remedies.

– Deborah S. Clements, MD, Northwestern Medical Group, Family Medicine

Why does your nose run when it’s cold?

Even if you’re not sick, your nose runs when it’s cold. Why? from www..com

David King, The University of Queensland

This is an article from I’ve Always Wondered, a new series where readers send in questions they’d like an expert to answer. Send your question to [email protected]

Why does your nose run when it’s cold? It seems counterintuitive – Sonja Dominik

About 50-90% of people get a runny nose when it’s cold. We call this “cold-induced rhinitis”, or “skier nose”. People with asthma, eczema and hay fever seem to experience it more.

It’s the job of your nose to make the air you breathe in warm and wet so that when it gets to your lungs it does not irritate the cells. When inhaling air through the nose at subfreezing temperatures, the air in the back of the nose is usually about 26°C, but can be as high as 30°C. And the humidity of air at the back of the nose is usually around 100%, irrespective of how cold the air is we’re breathing in.

This shows the nose is very effective at making sure the air we breath becomes warm and wet before it reaches the lungs.

Read more – Health Check: what’s the right way to blow your nose?

So how does it do this? Cold, dry air stimulates the nerves inside your nose, which send a message through your nerves to your brain. Your brain then responds to this impulse by increasing the blood flow to the nose, and these dilated blood vessels warm the air passing over them. Secondly, the nose is triggered to produce more secretions via the mucous glands in order to provide the moisture to humidify the air coming through.

Treatment is usually just to carry a hanky or tissue! from www..com

The cold, dry air also stimulates cells of your immune system (called “mast cells”) in your nose. These cells trigger the production of more liquid in your nose to make the air more moist. It’s estimated you can lose up to 300-400mL of fluid daily through your nose as it performs this function.

Heat and water loss are closely related: heating the air in the nasal cavities means the lining of the nasal cavity (mucosa) becomes cooler than core body temperature; at the same time, water evaporates (becomes vapour) to make the air moist. Water evaporation, which requires large amounts of heat, takes heat from the nose, thus making it cooler.

In response, the blood flow to the nose increases further, as the task of warming the air that’s breathed in takes precedence over heat loss from the nose (the body’s normal response to cold is to shunt blood away from the surface to the deep vessels to minimise heat loss from the skin). So it’s a difficult balancing act to achieve the correct amount of heat and moisture lost from the nose.

Read more – I’ve always wondered: why is the flu virus so much worse than the common cold virus?

When the compensatory mechanism is a little too overactive, moisture in excess of that needed to humidify this cold, dry air will drip from the nostrils. Mast cells are usually more sensitive in people with asthma and allergies, and blood vessel changes more reactive in those who are sensitive to environmental irritants and temperature changes. So nasal congestion and even sneezing can be triggered by the cold air.

Treatment is usually simply to carry some tissues or a handkerchief. Although the use of anticholinergic (blocks nerve impulses) and anti-inflammatory nasal sprays such as Atropine and Ipratropium have been trialled with some success.

Medical student Caitlin Saunders also contributed to this article.

David King, Senior Lecturer, The University of Queensland

This article was originally published on The Conversation. Read the original article.

Why Does Your Nose Run When It’s Cold Outside?

Your nose: one minute it’s a passageway for pleasant scents and life-giving oxygen, and the next it’s nothing more than an inconvenient snot faucet. This is especially apparent during the winter months. If you’ve ever experienced mucus running from your nose in sub-freezing temperatures, than you’re familiar with cold-induced rhinorrhea.

Rhinorrhea is the fancy medical term for a runny nose, and it can be caused by several different factors. In the case of cold-weather snot, there are two major culprits to blame: biology and physics.

On the bodily side of things, your nose works overtime when it’s cold outside to make sure the air you inhale is suitable for your sensitive lung tissue. Air that’s cold also tends to be very dry, so in order to humidify it, the nose ups its fluid production. This often leads to excess mucus, which ends up on your face instead of inside your nostrils.

The second factor can be explained by thermodynamics. A small part of every breath we exhale is water vapor. This can be observed firsthand in frigid temperatures: When the warm air from our bodies is expelled into the cold it condenses into a cloud of tiny droplets, allowing us to “see” our breath. This same principle is partly responsible for your runny nose. When the warm air inside your nostrils confronts cold temperatures, the moisture comes together to form larger, heavy droplets that contribute to the mucusy mess.

People who exercise in the cold are especially susceptible to a runny nose triggered by those low temperatures. The condition even has a name—”skier’s nose” (which admittedly sounds much sexier than “snot-covered face syndrome”). To learn more about unusual nasal behaviors, check out our Big Question about why your nose gets stuffy one nostril at a time.

Why Does Your Nose Run When It’s Cold?

As the old joke goes, “If your nose runs, and your feet smell, you’re built upside down!” Kidding aside, there are many reasons we get runny noses — technically known as rhinorrhea. When you have a cold or the flu, the mucous membranes that line the cavities in your nose produce a combination of mucus and fluid designed to fight off and wash away the germs. The nose also produces extra mucus after exposure to an allergen, whether it’s pollen, animal dander, or something else. Crying hard can also cause excess liquid to drain from the duct in the inner corner of the eyelid into the nasal cavities and out through the nose.

But why does your nose run when you’re out on a chilly winter day, even when you’re not sick or upset?

Your Nose at Work

Our noses warm and humidify — add moisture to — the air we breathe as it travels down into the lungs. So when you inhale cold, dry air, the moist tissue inside the nose automatically increases fluid production to do its job of protecting sensitive lung tissue. But when there’s too much fluid, the excess tends to drip out, creating a runny nose.

Winter has other effects that make it more likely you’ll have a runny nose. Cold temperatures can cause the small water droplets inside the moist nose to join together, forming big, heavy drops of water that can also drip from your nostrils. And cold air also speeds up mucus production.

QotW – Why does my nose run when it’s cold?

Neil – This common condition our cyclist is describing is known as ‘skier’s nose’ or ‘cold induced rhinorrhea.’ Rhinorrhea is the medical term for a runny nose and you may be more likely to suffer from this if you have hay fever or asthma.

The nose is like an air conditioning unit for the lungs. This involves heating and humidifying the air that we breathe as well as filtering out any impurities.

Izzie – There are two reasons for experiencing a runny nose when the air is cold and dry…

Neil – This cold dry air requires a greater amount of heating and humidification to protect the lungs. The blood vessels in the nose expand to increase the surface area for heating which is why our noses feel blocked and the mucus glands lining the nose produce more runny mucus for humidification; hence that snotty drip.

The second factor is that the air that we exhale is warm and moist. When this saturated humid air hits the cold temperatures towards the nostril, water condenses and drips out of the nose. The effect is like steam condensing on a cold bathroom window.

Izzie – So what can be done to prevent this nasal niggling short of becoming a dry nose couch potato or relocating with Mark Cavendish to somewhere warm for winter training?

Neil – Simple measures include carrying industrial quantities of tissues or protecting the nose with a scarf or buff. The latter not only results in less running but also collects any unwanted drips. Afterall, the nose is capable of producing a pint of snot per day.

Certain types of medication may also be beneficial if the rhinorrhea is particularly troublesome. These include nasal decongestants that limit the blood vessels’ dilation and other medicines that reduce the amount of mucus that’s trying to escape from your nose. It is important to point out however that their use should only ever be for short periods of time as long term use can result in unwanted side effects.

Izzie – Thanks Neil for sniffing out an answer. Next time we dig into this question from Eamon:

If someday we manage to travel to another planet and discovered aliens, what is the likelihood that we could eat them?

Why your nose runs when it’s cold outside

  • A runny nose is common when we’re sick, but it can come unexpected when we’re perfectly healthy.
  • So why do we get runny noses in the middle of summer or in the winter when we don’t have a cold? NYU otolaryngologist Dr. Erich Voigt says it has to do with the temperature of the air we breathe.
  • In the video above, Dr. Erich explains what’s actually happening in your nose.

Following is a transcript of the video.

Dr. Erich Voigt: What is our nose doing? It’s actually able to take air that might be zero degrees or 100 degrees, and as you breathe it in, it gets the air to body temperature. The nose is probably one of the least appreciated organs in the body. The nose’s job is unbelievable when you start to think about it.

So, we breathe in liters and liters of air. And what is our nose doing? It’s actually able to take air that might be zero degrees or 100 degrees, and as you breathe it in, it gets the air to body temperature. The air could be very dry or very moist with humidity. It actually brings the air to a particular state of humidity, and it filters all the particles that we’re breathing in.

It does this through massive amounts of blood flow through the nasal membranes. These membranes are very reactive, they react to temperature changes, they react to particulate matter in the air, and the blood flow will actually change very dramatically inside of the nose. With these extreme changes in temperature, from hot to cold, the blood flow changes, and with that comes changes in the flow of mucus.

So, one’s nose may run watery when we’re in really cold temperatures because the nose is actually trying to moisturize and heat that air. It’s using blood flow and mucus to do the job.

EDITOR’S NOTE: This video was originally published on August 25, 2016.

The nose is more than just a cosmetic appendage. It is responsible for filtering out the bad stuff that could make us sick and in the face of cold, dry air, ensuring that the lungs stay moist and supple.

When the temperature dips—say below 40 degrees—and the air becomes crackly with static, the nose begins working overtime to add humidity. The reaction—called rhinorrhea—can be almost instantaneous. Step outside and a river will start to flow.

“The compensatory action of the nose is to produce more mucous and more liquid to keep the nasal tissue hydrated and moist,” says Mitchell H. Grayson, a pediatric allergist and immunologist at the Medical College of Wisconsin in Milwaukee.

It’s essentially a nervous system response, mediated by chemical neurotransmitters that control the glands that produce mucous, says Grayson. It’s the same system that causes the mouth to water in anticipation of a meal.

The second cause of a cold-air-induced runny nose is simple condensation. The air inside the nose is kept at about 96 degrees F, says Grayson. When that warm air runs smack up against cold air, the reaction is moisture. That condensation—essentially water—joins with the mucous and adds to the outward flow.

It may be prodigious, but it will be generally a thin flow. “It’s not the stuff you see when you have a cold,” says Grayson. The fluid has to keep nasal tissue, and hence, the lungs moist, and “thick goopy mucous isn’t going to do that,” because that will merely just stop up the lung tissue, he says.

Heating the air and mucous production are among the nose’s primary activities. Usually, only one nostril is wide open at any given time, with the closed side doing the work. Every four hours or so, the two nostrils switch, with the closed side opening and the open side closing. The warm, humid air is sent to the lungs. Without moisture, the lungs will constrict and become damaged, says Grayson.

Mouth breathers pay the price of bypassing the nose—a sore throat brought on by the dry air.

Breathing through a scarf or bandana in cold air will help the nose do its job—and cut down on the outward nasal flow.

It’s your turn to Ask Smithsonian.

Chronic Rhinorrhea (Runny Nose)

How is rhinorrhea treated?
Once the source of the runny nose is found, treatment can include watchful waiting, washing the nose with nasal rinses, medications taken by mouth or sprayed into the nose, or even surgery.

What are the long-term effects of rhinorrhea?
Depending on the source of the runny nose, the long-term effects can vary. Nasal irritation and nasal obstruction can impact a child’s quality of life if it is longstanding. An obstructed nasal passageway can affect sleep quality. Breathing from the nose is also important for facial development in childhood. Rarely, acute infections of the sinuses can lead to more serious infections if left untreated. Nasal obstruction and rhinorrhea may impact the health of the ears and hearing as the drainage pathway for the middle ear is through the back of the nose (nasopharynx).

Side view of the nasal cavity showing the bony structures inside the nose.

Side view showing where adenoids lay in the back of the nose (nasopharynx). Adenoids are made of the same type of tissue, called lymphoid tissue, as the tonsils in the throat. This tissue can also be found in the back of the tongue, called lingual tonsil.

Front view showing where adenoids are in the back of the nose, just above the mouth palate. The back of the nose drains into the back of the throat. This picture also demonstrates how these parts work together, in what is often called a “lymphatic ring”.

Learn more about Pediatric Otolaryngology or call us at (650) 724-4800 for more information.

With the proper gear and the right attitude, wintertime running can be magical. What’s not magical: the free-flowing fountain of snot that typically accompanies these workouts. Luckily, there are several things you can do before, during, and after a run to aid your sniffling sniffer.

But first, some background on exactly why this happens: The membranes in our nasal passages help humidify air as it enters, explains Clifford Stark, an osteopathic physician specializing in sports medicine. In the winter, the air is colder and drier than summer months, so the nose has to work doubly hard at humidifying. Exercising exacerbates the issue, since heavier breathing dramatically increases exposure to the cold, dry air. The result? Your schnoz goes into overdrive trying to provide enough moisture and thus dumps extra mucus (in sometimes a seemingly endless supply). Here are Stark’s—and three other experts’—tips for navigating these sticky situations.

Related: Why Breathing Cold Air Hurts

Before Your Run: Humidify

Hilmar Hilmar

The night before a chilly al fresco run, bust out your humidifier and leave it on while you sleep. “This will keep the membranes moist so that they will be healthier before going out into the cold, dry air,” explains Stark. And if you forget to turn it on overnight, you can still use it an hour or two before your run.

While there’s no hard data supporting the benefits of humidifying immediately before exercise, “it follows the same general principles that it will probably help provide some moisturizing protection to the membranes, and certainly shouldn’t have any detrimental effects,” says Stark.

Neti Pot It Up

Mitch Mandel

The neti pot—an irrigation tool used to flush out the nasal cavity with saline solution—can help clear and moisturize a stuffy nose so that it’s less likely to run incessantly once exposed to the elements. Jon Grant, a runner and St. Vincent Sports Performance trainer who’s worked with both everyday athletes and Olympians, relies on this home remedy directly before exercising. “The closer you use it to the run, the more effective it can be,” he says, noting it can be used again, post-run, to flush out any remaining residue.

Try a Saline Nasal Spray

Pixland / Thinkstock

These soothing, moisturizing sprays can be used as often as necessary, advises Stark, especially in cold, dry weather when the mucous membranes are extra dry and irritated. Runners can take a dose before— and even during—exercise (the small containers are easily totable). Stark recommends consistent usage as the most effective method for maintaining a healthy honker, but notes that “every bit helps.”

Address Any Pre-Existing Issues

In some cases, cold weather isn’t the only culprit. Upper respiratory infections, allergies, pollutants, smoke and other chemical sensitivities that cause nasal irritation will likely worsen a runny nose in cold weather. “Treating these conditions before going outside will likely help minimize this effect,” says Stark, recommending runners check in with their doctors if they suspect an underlying issue.

During Your Run: Swath Your Nose

Laszlo Ilyes via Flickr and licensed under Creative Commons Attribution

Covering your nose and the lower half of your face with fabric “will help to maintain humidity in the air entering the nose, which will minimize irritation of the membranes and also keep the nose from having to work so hard to humidify the air,” explains Stark.

Kyle Larson, a runner with the Fleet Feet Sports racing team in Chicago, favors a Buff pulled up over his nose or a Smartwool Balaclava. Another option: the Smartwool Mid 250 Neck Gaiter, which “warms the neck and can easily be used to wipe the snot away,” says Lyndsey Baum, product buyer at Fleet Feet Sports. (It’s also machine washable so you can erase the evidence post-run.)

Dress Up Your Digits

Mitch Mandel

Sometimes, despite your best efforts, the floodgates open anyways. In such cases, Larson turns to his hands for help. “The nice thing about most running gloves is they will have a patch of soft fleece material on the top of the thumb so you can wipe the snot off your nose,” he says (adding, “I know it’s gross.”) Two such options with this built-in “snot spot:” the Manzella Hatchback Gloves and the Manzella Power Stretch Ultra Touch Tip Gloves.

Related: Layer up With New Running Gear

Launch a Snot Rocket

Grizzzley via Flickr and licensed under Creative Commons Attribution

A less stylish—but equally effective—solution: the snot rocket, also known as the “farmer’s blow.” Grant describes this technique as “my absolute favorite that I use almost every time I run.” Check out the below video for step-by-step (er, blow-by-blow) instructions.

After Your Run: Let Your Schnoz Rest


Post-runny nose run, Stark warns against blowing your nose too aggressively as this may cause further irritation. As a solution for more severe cases, he recommends an ipratropium bromide nasal spray, which can be used to prevent or treat the symptoms of runny nose. It typically works within 15 minutes or less, and can last a few hours, depending on the dosage. One caveat: it can cause a few side effects (including excessive dryness and irritation), so he advises a doc consult before using.

Jenny McCoy Contributing Writer Jenny is a Boulder, Colorado-based health and fitness journalist.

Why Does Cold Weather Cause Runny Noses?


Now, your runny nose may not seem like rocket science, but it does involve a bit of thermodynamics. What is it about the chilly winter breeze that makes tissues a cold weather essential? Earlier, I braved the great outdoors – and I know you can tell – to bring you this week’s “Science Out of the Box.”

(Soundbite of music)

LYDEN: I’m standing on the roof of NPR headquarters in Washington, D.C. It’s chilly. It’s about 35 degrees or so. But earlier this week, especially on the National Mall, it was really cold. And I was suffering from what the experts call cold-induced rhinorrhea, and that colloquially is known as a runny nose.

We wanted to know why our noses always run in cold weather. So we called on Dr. Andrew Lane. He’s the director of the Johns Hopkins Sinus Center, and he’s standing outside his office in Baltimore. Welcome, Dr. Lane.

Dr. ANDREW LANE (Director, Sinus Center, Johns Hopkins University): Hi, Jacki. Thanks.

LYDEN: Well, I have been wondering this, really, since the first of the year. Why is it that our noses run in the cold whenever we step outside?

Dr. LANE: Well, it’s really a combination of two things. It’s part respiratory biology and part of it is physics, or thermodynamics. One of the main functions of the nose is to warm and humidify the air that we breathe so that when it reaches your lungs, it’s nice and conditioned. And in order to do this, the nose has to add some moisture to it.

When it’s very cold out, the air is usually dry as well, and the nose is really working overtime to add some fluid. And there are reflexes that are in place that allow the nose to increase its fluid production. And if it really makes a lot of fluid, then it starts to run out of the end of your nose.

LYDEN: So, it’s a good reaction. It should happen.

Dr. LANE: Right. It’s a normal reaction sort of taken to the extreme. Now the other side of it is the physics part. And this is sort of a good day for this, I suppose. Can you see your breath when you breathe there?

LYDEN: I can.

Dr. LANE: What’s happening is that the warm air that you’re breathing is condensing in the cold air, so you see it as little droplets of water. And that’s because cold air can’t hold as much moisture as warm air. When you breathe that air back out, it comes to the very tip of your nose where the nose is cold and that fluid is going to recondense onto the surface of the nose and that will also run out.

LYDEN: So kind of a double whammy on the old nose between the biology and the physics.

(Soundbite of laughter)

Dr. LANE: Yeah.

LYDEN: Andrew Lane is the director of the Johns Hopkins Sinus Center. Thanks so much for joining us. I think we should both go inside and get warm now and have a cup of cocoa or echinacea.

Dr. LANE: I’m with you, Jacki. Thanks.

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