Runny Nose and Sneezing

A runny nose and sneezing are among the most common symptoms people experience. They are usually caused by a viral cold or allergy and often improve on their own. In a common cold, nasal symptoms typically last up to 10–14 days but should gradually get better over that time.

However, symptoms that persist without improvement, affect only one nostril, follow a head injury or nasal or sinus surgery, or occur with fever, facial swelling, visual symptoms, breathing difficulty, or a weakened immune system need medical review. This guide explains the most common causes, how to tell them apart, and when to see a doctor.
 

Key Facts at a Glance

What Causes a Runny Nose and Sneezing?

A runny nose and sneezing can occur for many reasons. The same symptoms may be caused by infection, allergy, irritants, medications, structural nasal problems, or rarely a cerebrospinal fluid (CSF) leak. Sometimes more than one factor is present simultaneously. For example, a viral cold in someone who already has allergic rhinitis. The pattern of symptoms helps guide the likely cause, but persistent, severe, one-sided, or unusual symptoms need medical assessment rather than continued self-treatment.
 

1. Viral Upper Respiratory Infections — The Common Cold

The common cold is one of the most frequent causes of runny nose and sneezing. Many viruses can cause it, including rhinoviruses (accounting for roughly 30–50% of cases), coronaviruses, RSV, parainfluenza viruses, and adenoviruses.

A cold often follows this typical pattern:

• Days 1–2: clear watery discharge, sneezing, mild sore throat
• Days 3–5: discharge may become thicker and turn white, yellow, or green
• Days 7–14: symptoms gradually improve; nasal symptoms and cough can persist for up to 10–14 days
   

Does green or yellow mucus mean I need antibiotics?

Usually, no. Yellow or green mucus is a normal part of the immune response to viral infection and does not by itself mean bacterial infection. Antibiotics should not be used for an uncomplicated cold.

Seek medical advice — not antibiotics — if:

• Symptoms last more than 10 days without any improvement
• Symptoms worsen after initially getting better (sometimes called “double worsening”)
• Symptoms are severe from the start, with high fever and marked facial pain or facial swelling
• There is swelling around the eye, visual changes, or severe headache

A doctor will assess whether bacterial sinusitis is likely before considering antibiotics. Unnecessary antibiotic use contributes to antibiotic resistance.

Influenza can also cause nasal symptoms but typically presents with sudden-onset high fever, severe body aches, significant fatigue, and headache. Antiviral medicines such as oseltamivir may be considered for selected patients, particularly those at higher risk of complications. Antiviral treatment should be assessed by a clinician and works best when started early.

SARS-CoV-2 infection can cause runny nose and sneezing. Testing may be appropriate after exposure, during local outbreaks, or in people at higher risk of severe illness.
 

2. Allergic Rhinitis

Allergic rhinitis occurs when the immune system reacts to airborne allergens such as dust mites, pollen, mould, cockroach allergens, or animal dander. It may be seasonal (triggered by outdoor pollen) or present throughout the year (triggered by indoor allergens such as dust mites or pet dander).
 

The Most Useful Clue: Itching

The hallmark of allergic rhinitis and the most helpful feature for distinguishing it from a cold or non-allergic rhinitis is itching. Allergic rhinitis commonly causes:

• Clear, watery nasal discharge
• Repeated sneezing, often in clusters
• Blocked nose
• Itching of the nose, eyes, throat, or palate
• Red, watery, or itchy eyes (allergic conjunctivitis)

Symptoms may worsen after exposure to dust, pets, damp rooms, pollen, cleaning activities, or seasonal changes. Allergic rhinitis can also worsen asthma control, affect sleep, impair concentration, and reduce school or work performance. People with allergic rhinitis and asthma particularly benefit from effective rhinitis treatment.
 

3. Non-Allergic Rhinitis

Non-allergic rhinitis causes runny nose, congestion, or sneezing without an allergic trigger. Allergy tests are negative, and prominent itching or eye symptoms are less common than in allergic rhinitis.

Common types include:

• 1. Vasomotor Rhinitis: Triggered by temperature changes, strong smells, smoke, humidity, alcohol, or spicy food. Symptoms occur because nasal nerves and blood vessels are overly reactive to these stimuli, not because of an allergy.
• 2. Hormonal Rhinitis: Nasal congestion and discharge may occur during pregnancy, affecting a significant proportion of pregnant women. Pregnancy rhinitis usually improves after delivery.
• 3. Medication-Related Rhinitis: Some medicines can worsen nasal symptoms, including certain blood pressure medicines (alpha-blockers, some calcium channel blockers) and NSAIDs in susceptible people. Do not stop prescribed medicines without medical advice; discuss possible alternatives with your doctor.
• 4. Rhinitis Medicamentosa: Rebound nasal blockage caused by using topical nasal decongestant sprays — such as xylometazoline or oxymetazoline — for longer than recommended. This is distinct from steroid nasal sprays or saline sprays, which do not cause this rebound effect.
• 5. Occupational Rhinitis: Symptoms related to workplace exposure, such as flour dust, chemicals, latex, animal proteins, or fumes. A useful clue is that symptoms typically improve during weekends or time away from work and return on working days.
   

4. NARES — Non-Allergic Rhinitis with Eosinophilia

NARES is a form of non-allergic rhinitis that can look very similar to allergic rhinitis. It may cause repeated sneezing, watery discharge, blocked nose, and reduced sense of smell, but allergy testing is negative.

It is usually identified by an ENT specialist or allergist, sometimes with a nasal smear that shows increased eosinophils, a type of immune cell. NARES often responds well to intranasal corticosteroid sprays and may be associated with a higher risk of developing nasal polyps over time, making accurate diagnosis worthwhile.
 

5. Structural and Anatomical Causes

Structural problems in the nose or surrounding structures can contribute to chronic blockage, discharge, mouth breathing, recurrent sinus symptoms, or reduced sense of smell.
 

Nasal Polyps

Soft, non-cancerous swellings of the nasal or sinus lining, often linked with chronic rhinosinusitis, asthma, or aspirin/NSAID sensitivity. Symptoms include persistent blocked nose, runny nose, and reduced or absent sense of smell. Treatment usually begins with regular intranasal steroid sprays; persistent or severe cases may need ENT evaluation and sometimes surgery.
 

Deviated Nasal Septum

The partition between the two nostrils is positioned off-centre. A significant deviation can cause one-sided nasal blockage and may contribute to recurrent sinus problems. It is not usually a direct cause of sneezing.
 

Adenoid Hypertrophy

Enlarged adenoids in children can cause persistent nasal blockage, mouth breathing, snoring, recurrent ear infections, and nasal discharge.
 

Nasal Foreign Body

A common and commonly missed cause of one-sided foul-smelling discharge in young children. Any child with persistent discharge from only one nostril should be assessed by a doctor. Do not attempt to remove a suspected foreign body at home using cotton buds or instruments, as this may push it deeper or cause injury.
 

Adult Unilateral Nasal Symptoms

Persistent one-sided discharge, blockage, or bleeding in an adult needs medical assessment to exclude a mass or other serious cause. This should not be attributed to allergy or rhinitis without examination.
 

6. Cerebrospinal Fluid Leak — Rare but Serious

When to Seek Urgent Care

A CSF leak is a rare but important cause of clear watery discharge from one nostril. It can occur after head injury, nasal surgery, sinus surgery, or skull-base surgery, and rarely because of raised pressure around the brain.

• Clear watery discharge from one nostril, especially after head injury or nasal/sinus/skull-base surgery
• Discharge that increases when bending forward
• A salty or metallic taste at the back of the throat

Seek urgent specialist care if these features are present. A CSF leak carries a risk of bacterial meningitis. Do not blow the nose forcefully or strain until you have been reviewed. Diagnosis involves specialist evaluation, testing of the nasal fluid for CSF-specific markers (not a routine blood test), and imaging.
 

7. Environmental and Physical Triggers

Some people develop sneezing or watery nasal discharge after exposure to irritants or environmental changes. This does not always indicate allergy.

Common triggers include:

• Cold or dry air
• Smoke, perfumes, paint fumes, cleaning products, or strong odours
• Dust and air pollution
• Sudden bright light or sunlight, known as photic sneezing — a harmless inherited reflex affecting some people

Avoiding known triggers, improving ventilation, and using protective measures during highxposure situations may help reduce symptoms.
 

8. Gustatory Rhinitis — Food-Triggered Runny Nose

Gustatory rhinitis causes watery nasal discharge while eating, especially with hot or spicy foods. It is usually not related to food allergy. It happens because nerve pathways that stimulate digestion can also activate nasal glands.

It is more common in older adults and is generally harmless. If symptoms are frequent or troublesome, a doctor may prescribe ipratropium bromide nasal spray to use before meals.
 

9. Atrophic Rhinitis

Atrophic rhinitis is a chronic condition in which the nasal lining becomes thin and dry. It may cause crusting, a sensation of blockage despite open nasal passages, foul smell, and thick discharge. It can occur after extensive nasal surgery and may also be associated with chronic infection or other local factors.

Persistent crusting or foul-smelling nasal discharge should be assessed by an ENT specialist rather than repeatedly self-treated as infection. Treatment depends on the cause and may include nasal cleaning, moisturising treatments, and targeted medical therapy.
 

How to Tell the Causes Apart

Because many conditions produce similar symptoms, the character of the discharge, the presence of itching, which nostril is affected, and what triggers symptoms are the most useful clues. The table below provides a quick reference guide. It should guide you towards the likely cause, not replace a clinical assessment.
 

When to See a Doctor

Seek urgent care for any of the following:

• Clear watery discharge from one nostril after head injury, nasal surgery, sinus surgery, or skull-base surgery — possible CSF leak
• Swelling or redness around the eye, or any visual changes
• Severe headache, neck stiffness, or confusion — possible meningitis
• Breathing difficulty or a very unwell child
• Baby under 3 months with nasal symptoms and feeding difficulty or breathing difficulty

See a doctor promptly if you notice:

• Symptoms lasting more than 10–14 days without improvement
• Symptoms that improve and then suddenly worsen again
• Severe fever, facial pain, or pressure that is persistent or worsening
• Discharge or bleeding from only one nostril
• A child with foul-smelling one-sided nasal discharge
• Persistent loss of sense of smell, especially if associated with blocked nose or sinus symptoms
• Symptoms lasting 12 weeks or more, or symptoms affecting sleep, school, work, or asthma control
• Nasal symptoms in a person with weakened immunity, significant chronic illness, or pregnancy
• Recurrent or unusual nasal symptoms in an older adult, particularly if one-sided or blood-stained
   

Treatment Overview

Common Cold

There is no cure for a common cold; treatment is supportive and aimed at managing symptoms comfortably.

• Drink adequate fluids and rest as needed
• Use saline nasal drops or spray to ease congestion; these are safe for all ages including infants
• Use paracetamol or ibuprofen for fever or discomfort, if appropriate for age and health condition
• Avoid antibiotics unless a doctor has assessed and suspects bacterial infection

Topical nasal decongestant sprays (such as xylometazoline) may relieve congestion in adults and older children but should be limited to 3–5 days. Do not use decongestant sprays in children under 6 years unless specifically advised by a doctor. Avoid over-the-counter cold combination medicines in young children.

If using nasal irrigation devices such as a neti pot, always use sterile, distilled, or previously boiled and cooled water. Tap water is not safe for nasal irrigation.
 

Allergic Rhinitis

Treatment depends on the severity of symptoms and the identified triggers:

• Reduce allergen exposure where practical, particularly dust mites, dampness, mould, and pet dander
• Use intranasal corticosteroid sprays — such as fluticasone, mometasone, or budesonide — for persistent symptoms; these work best when used regularly and with correct technique
• Use second-generation oral antihistamines — such as cetirizine, loratadine, levocetirizine, or fexofenadine — for sneezing, itching, and watery discharge
• Consider allergy testing if symptoms are persistent, severe, or unclear
• Consider allergen immunotherapy only after specialist evaluation and confirmation of the relevant allergy

Intranasal corticosteroid sprays are generally safe at recommended doses. However, prolonged use, use in children, use during pregnancy, or recurrent nosebleeds while using them should be discussed with a clinician.
 

Non-Allergic Rhinitis

Treatment depends on the specific type and trigger:

• Vasomotor rhinitis: avoid known triggers where possible; saline spray, intranasal ipratropium for watery discharge, intranasal corticosteroids, or intranasal antihistamines may help selected patients, as guided by a doctor.
• NARES: intranasal corticosteroid sprays are commonly used and should be guided by an ENT specialist or allergist.
• Medication-related rhinitis: do not stop prescribed medicines on your own; discuss possible alternatives with your doctor.
• Rhinitis medicamentosa: rebound congestion usually improves after stopping or gradually reducing the topical decongestant spray. This can be difficult without support. A doctor may recommend intranasal steroid support during withdrawal. Oral corticosteroids should only be used under medical supervision.
   

Special Considerations

Children

Young children commonly have several colds each year, especially after starting daycare or school. This is generally normal and does not by itself indicate a problem with the immune system.

Important points for children:

• Antibiotics are not needed for uncomplicated viral colds
• Saline nasal drops or spray are safe and helpful for babies and young children
• Avoid topical nasal decongestant sprays in children under 6 years unless specifically advised by a doctor
• Avoid over-the-counter cold combination medicines in young children unless prescribed
• Allergic rhinitis may coexist with asthma or eczema, treating nasal symptoms well may also improve asthma control
• One-sided foul-smelling discharge in a child: always consider a foreign body; do not attempt home removal
   

Seek Urgent Medical Care for a Child with:

• Breathing difficulty or rapid breathing
• Poor feeding or signs of dehydration
• Unusual drowsiness or difficulty waking
• Persistent high fever or high fever with facial swelling
• Swelling or redness around the eye
• Any symptoms in a baby under 3 months, especially with breathing difficulty or poor feeding
   

Pregnant Women

Nasal congestion and runny nose are common during pregnancy because of hormonal and vascular changes. Non-drug measures are preferred first:

• Saline nasal spray or rinses
• Humidification if the air is dry
• Avoiding smoke, dust, and strong odours
• Sleeping with the head slightly elevated if congestion is troublesome at night

If medication is needed, discuss it with your obstetrician or physician. Intranasal budesonide is commonly considered compatible with pregnancy when clinically needed. Oral decongestants such as pseudoephedrine are generally avoided in the first trimester and should not be used without medical advice, particularly in women with high blood pressure or pregnancy-related vascular risks. Pregnancy rhinitis usually resolves after delivery.
 

Older Adults

Runny nose is common with ageing because of changes in nasal lining, autonomic nerve sensitivity, and increased medication use. Gustatory rhinitis is also more prevalent in older adults.

Older adults should avoid casual use of sedating (first-generation) antihistamines, as these can cause drowsiness, confusion, urinary problems, and an increased risk of falls. New, persistent, or one-sided nasal symptoms, especially bleeding, blockage, foul discharge, or facial pain should be assessed by a doctor or ENT specialist without delay.
 

Frequently Asked Questions

My nose runs every morning when I wake up. Why?

Morning runny nose may be due to non-allergic rhinitis, house dust mite allergy (dust mites are concentrated in bedding), dry or cold air, mould in the bedroom, or chronic nasal inflammation. If it happens daily, it is worth noting potential triggers such as bedding type, air-conditioning, pets, dampness, and the morning temperature. See a doctor if it persists, affects sleep quality, or occurs alongside blocked nose, wheeze, smell loss, or sinus discomfort.
 

Is green or yellow discharge a sign I need antibiotics?

Usually, no. Yellow or green mucus commonly occurs during viral colds as a normal part of the immune response and does not automatically indicate bacterial infection. Antibiotics may be considered only after medical assessment if symptoms last more than 10 days without any improvement, worsen after initially getting better, or are associated with significant fever, severe facial pain, facial swelling, or complications. Do not self-prescribe antibiotics for coloured nasal discharge.
 

Can eating spicy food really make your nose run?

Yes. This is called gustatory rhinitis. Hot or spicy foods stimulate nerve pathways that activate nasal glands, causing watery discharge. It is usually not related to food allergy and is generally harmless. If it is frequent or bothersome, a doctor may prescribe ipratropium bromide nasal spray to use before meals.
 

I have had a runny nose for three months. Could it be allergies?

Possibly, but symptoms lasting three months or more need proper clinical evaluation rather than continued self-treatment. By this duration, symptoms meet the threshold for chronic rhinosinusitis assessment. Causes to consider include allergic rhinitis, non-allergic rhinitis, chronic rhinosinusitis, nasal polyps, medication-related rhinitis, or structural nasal problems. See an ENT specialist or allergist, especially if symptoms are one-sided, blood-stained, associated with smell loss, facial pain, asthma, or poor sleep.
 

Can you become ‘addicted’ to nasal decongestant sprays?

It is not addiction in the conventional sense, but a real problem called rhinitis medicamentosa (rebound congestion) can develop with prolonged use. Topical nasal decongestant sprays such as xylometazoline or oxymetazoline should usually be used for no more than 3–5 days. Longer use causes the nasal blood vessels to become reliant on the spray. When it wears off, congestion returns worse than before. Treatment involves stopping or gradually reducing the spray, often with medical support and an intranasal steroid spray. This is different from saline sprays or steroid nasal sprays, which do not cause this rebound effect.
 

My child has had a smelly discharge from one nostril for two weeks. Should I be worried?

Yes. Persistent foul-smelling discharge from one nostril in a child should be treated as a possible nasal foreign body until examined by a doctor. Children often insert small objects into the nose and may not remember or disclose it. The object causes localised infection, producing a smelly one-sided discharge. See a doctor promptly. Do not attempt to remove the object at home with cotton buds or instruments, as this may push it deeper or cause bleeding.
 

Key Takeaways

• Runny nose and sneezing are commonly caused by viral infections or allergies and usually improve on their own, especially in uncomplicated common colds.
• In a common cold, nasal symptoms may last up to 10–14 days and often progress from clear discharge to thicker yellow or green mucus before improving.
• Yellow or green nasal mucus does not automatically mean a bacterial infection or the need for antibiotics.
• Itching of the nose, eyes, throat, or palate is a key clue suggesting allergic rhinitis rather than a viral cold or non-allergic rhinitis.
• Non-allergic rhinitis can be triggered by smoke, perfumes, temperature changes, spicy foods, pregnancy, medications, or overuse of nasal decongestant sprays.
• Persistent one-sided nasal discharge, especially if foul-smelling in a child or blood-stained in an adult, requires medical evaluation to rule out a foreign body or more serious causes.
• Clear watery discharge from one nostril after head injury or nasal/sinus surgery may indicate a cerebrospinal fluid (CSF) leak and needs urgent specialist assessment.
• Nasal decongestant sprays such as xylometazoline or oxymetazoline should generally not be used for more than 3–5 days because prolonged use can cause rebound congestion.
• Saline nasal sprays, intranasal corticosteroid sprays, antihistamines, trigger avoidance, and adequate hydration are commonly used to manage symptoms depending on the underlying cause.
• Medical attention is needed for symptoms lasting more than 10–14 days without improvement, severe fever or facial swelling, breathing difficulty, persistent smell loss, eye symptoms, or symptoms in very young infants.