Why Does Your Nose Run in the Cold? Cold-Induced Rhinitis Explained
Your nose runs in the cold because its job is to warm and moisten every breath before it reaches the lungs, and cold air is dry. To cope, the lining produces more fluid, and the nerves that control the nasal glands react to the cold itself by switching secretion on. A little of the moisture in your warm breath may also condense at the cold tip of the nose on the way out. The result is a clear drip that starts within minutes of stepping outside and stops soon after you warm up.
On its own, this is not a cold and not an allergy. Doctors call it cold-induced rhinitis, a form of non-allergic rhinitis. It is harmless in itself. If the drip continues indoors, comes with itching or sneezing, or is thick or coloured, something else is going on.
This guide explains the mechanism, who gets it most, how to tell it from the other causes of a winter runny nose, and what helps.
What the nose does with cold air
Air arriving at the lungs needs to be close to body temperature and fully humidified. The nose does most of that work in the fraction of a second a breath takes to pass through. The lining has a rich blood supply to add heat and a layer of mucus to add moisture.
Cold air holds very little water, even on a damp day, so almost all the moisture in each breath has to come from the lining. On a cold day the lining works harder, the blood vessels open to deliver heat, and the glands produce more fluid than the air can carry away. The excess runs forward and drips.
The nerve reflex
The nasal lining is also wired with cold-sensitive nerves. In people who get a cold-weather drip, these nerves appear to trigger a reflex that switches the mucus glands on. Spicy food and hot drinks set off the same reflex. The NHS lists changes in the weather, such as temperature or humidity, among the triggers for non-allergic rhinitis.
Condensation
Warm, moist air leaving the lungs meets the cold tip of the nose on the way out. Some of that water vapour can condense on the cold tip of the nose, the same way your breath fogs on a cold morning. This probably adds a little to the drip, but the extra secretion and the nerve reflex do most of the work.
Who gets it most
Most people get some cold-weather drip. It is more noticeable in:
- Runners, cyclists and skiers. Fast breathing in cold air multiplies the moisture demand. Skiers call it "skier's nose".
- Older adults. The nasal lining thins, and the nerve reflex is thought to become more reactive with age. Our guide to why your nose runs more as you age covers this.
- People with non-allergic rhinitis who already react to spicy food, perfume or temperature changes.
- Anyone with a cold or allergy, because the lining is already inflamed and producing more mucus.
Is it the cold weather, a cold, or an allergy?
Three different things cause a runny nose in winter and they are easy to confuse. The timing tells them apart.
| Clue | Cold-induced rhinitis | A cold | Allergy |
|---|---|---|---|
| Starts | Minutes after going out in the cold | Over a day or two, often with a sore throat | Minutes after contact with a trigger, indoors or out |
| Stops | Soon after you warm up | After one to two weeks | When the trigger is gone |
| Mucus | Clear and watery | Often thickens and turns yellow or green | Clear and watery |
| Sneezing and itching | Little or none | Some sneezing early on | Frequent sneezing, itchy nose and eyes |
| Feeling unwell | No | Often, with aches or a mild fever | No |
If the drip carries on indoors with sneezing and itching, read our guide to telling allergies from a cold. If you only get it outdoors, you are reading the right article.
Are you allergic to cold weather?
Cold air itself is not an allergen, so a cold-weather drip is non-allergic rhinitis and antihistamines usually do little for it. The one condition that behaves like a cold allergy is cold urticaria, which affects the skin rather than the nose. Cold-exposed skin comes up in itchy, raised weals, and rarely the reaction spreads through the body. If that happens to you, see a doctor before you next swim in cold water. Call emergency services for faintness, facial swelling or breathing difficulty after cold exposure.
What helps
You cannot stop the nose doing its job, but you can reduce the demand on it and manage the drip.
Before you go out
- Wear a scarf, snood or buff over your nose and mouth. It traps warmth and moisture from your breath so each incoming breath is pre-warmed. For most people it is the simplest measure and usually the most effective.
- Use a saline spray before heading out. A moist lining copes better with dry air than a dry, irritated one.
- Warm up indoors first if you are exercising. Going from a warm house straight into hard breathing in cold air is the worst case.
While you are out
- Breathe through the nose rather than the mouth where you can. Mouth breathing bypasses the nose's warming and sends cold, dry air straight to the throat and lungs.
- Carry tissues and blow gently, one nostril at a time. Repeated hard blowing irritates the lining and can cause nosebleeds, which are already more likely in winter. Our guide to winter nosebleeds explains why.
- Slow down for the first few minutes of a run or ride so breathing builds gradually.
If it is a daily problem
For people whose nose runs heavily every time they go out, a doctor can prescribe an anticholinergic nasal spray. It works on the nerve reflex that switches the glands on, which is the mechanism behind cold-induced rhinitis. A doctor may suggest timing it before known triggers such as a cold walk or a run. It can cause nasal dryness and nosebleeds. Tell the prescriber about glaucoma, prostate problems and any other medicines you take. Steroid nasal sprays help some people with non-allergic rhinitis, particularly where blockage is part of the picture. A pharmacist or GP can advise which is suitable, and the NHS notes that a GP can prescribe stronger nasal sprays if pharmacy options do not help.
Decongestant sprays are not the answer. They shrink the lining for a few hours and, used for more than five days, cause rebound blockage.
For children, stick to a scarf, saline and gentle blowing, and ask a pharmacist before using any nasal spray. If you are pregnant or take medicines that dry the mouth or nose, ask a pharmacist or GP before starting any spray.
Runners and winter training
A runny nose on a cold run is normal and not a reason to stop. Breathing through the nose as much as pace allows warms the air, filters it and slows the drip. It takes practice. Our guide to nose breathing exercises for beginners builds the habit, and our article on nasal breathing for athletes covers how to hold it at higher effort.
Cold air can also trigger wheeze or a tight chest in people with asthma. A runny nose is harmless. A tight chest is not. Use your reliever as your asthma plan says, and get urgent help if it does not settle.
Does cold weather give you a cold?
Cold weather does not cause colds. Viruses do. Colds are more common in winter because people spend more time indoors together. Laboratory studies also suggest a cooler nasal lining defends itself less well against cold viruses. Our guide to protecting your nose from winter colds and flu covers what actually reduces the risk.
When to see a doctor
A clear drip that starts in the cold and stops indoors needs no medical attention. See a GP if a runny nose is constant regardless of temperature, or if it affects your sleep or daily life. Thick, coloured or bloodstained discharge, or discharge from one side only, also needs a check.
Seek urgent, same-day medical assessment for a clear, watery, one-sided drip that follows a head injury or sinus surgery. Be especially quick if it tastes salty or metallic, or comes with a severe headache or fever. This can be fluid leaking from around the brain.
Call your local emergency number for severe breathing difficulty, or swelling of the lips, tongue or throat.
Frequently asked questions
Why does my nose run when it's cold outside?
Cold air is dry, so the nose produces extra fluid to moisten it, and cold-sensitive nerves in the lining switch the mucus glands on. A little of the moisture in your breath may also condense at the tip. The drip is clear and stops once you warm up.
Is a runny nose in cold weather a sign of a cold?
Not on its own. A cold builds over a day or two, brings a sore throat or aches, and the mucus often thickens. A cold-weather drip starts within minutes outdoors, stays clear and stops indoors.
How do I stop my nose running in the cold?
Cover your nose and mouth with a scarf so the air you breathe in is pre-warmed, use saline before going out, breathe through your nose, and blow gently. For a heavy daily drip, a doctor can prescribe a spray that calms the nerve reflex.
Why does my nose run when I exercise in the cold?
Fast breathing multiplies the amount of cold, dry air the nose has to warm and moisten. The lining produces more fluid to keep up and the excess drips. A scarf or buff and a gradual warm-up reduce it.
Can you be allergic to cold weather or cold air?
A runny nose in cold air is non-allergic rhinitis, not an allergy. A rare skin reaction to cold, cold urticaria, causes hives rather than a runny nose and needs a doctor's assessment.
This article provides general information. A pharmacist or doctor should guide treatment, particularly for children, in pregnancy, or if you take other medicines.
