Postnasal Drip: Causes, Treatment and Home Remedies

What is postnasal drip?

The lining of the nose and sinuses produces one to two litres of mucus a day to trap dust, microbes and allergens and to humidify air. Normally, it drains into the throat and is swallowed without any awareness. “Postnasal drip” is the sensation that arises when the mucus becomes thicker, more abundant or when throat sensitivity increases. It is a symptom, not a disease; some doctors call the cluster of symptoms “upper airway cough syndrome”.

Symptoms

A sensation of mucus trickling or collecting in the back of the throat.
Frequent throat clearing and swallowing.
Cough, especially at night or on lying down.
Sore, scratchy or itchy throat; hoarse voice in the morning.
Bad breath and a bad taste.
Nausea in the morning from swallowed mucus, in some people.
Nasal congestion, sneezing or facial pressure, depending on the cause.

Causes

Allergic rhinitis: pollen, dust mites, pets, moulds.
Common cold and other viral infections.
Sinusitis, acute or chronic.
Non-allergic (vasomotor) rhinitis: triggered by temperature changes, strong smells, spicy food or smoke.
Dry air and dehydration that thicken mucus.
Deviated septum, nasal polyps or enlarged adenoids.
Pregnancy and hormonal changes.
Medicines: some blood pressure tablets and others.
Reflux (including LPR), which can feel like mucus in the throat. See LPR.

Home remedies that help

Saline nasal rinse or spray to thin and flush mucus and allergens (use distilled, sterile or boiled-and-cooled water).
Drink enough fluids to keep mucus thin.
Humidify the bedroom and use steam from a warm shower.
Sleep with your head raised on an extra pillow.
Avoid smoke, strong fragrances and known allergens.
Honey in warm water or tea to soothe the throat (not for babies under one year).
Resist constant throat clearing; sip water or swallow instead.
See also throat clearing (Spanish).

Medicines and when they help

Nasal corticosteroid sprays (fluticasone, mometasone, budesonide) are the most effective option for allergic rhinitis and persistent congestion; use daily and give them a week or two to work. Antihistamines help allergy, but older, sedating ones can dry mucus and thicken it. Decongestant sprays should be used no longer than 3–5 days. Ipratropium nasal spray may help runny nose in non-allergic rhinitis. Mucus thinners (guaifenesin) have limited evidence. Antibiotics are only for bacterial sinusitis. Check with a pharmacist or doctor before combining products.

Postnasal drip in children

Children often have nocturnal cough from mucus after colds or allergies. Saline drops or sprays, humid air, fluids and honey (over one year) can help. Do not give over-the-counter cough and cold medicines to children under six unless advised. Consult the doctor if the cough lasts more than 3–4 weeks, if the child snores or breathes through the mouth, or if there are repeated ear or sinus infections, which may mean enlarged adenoids.

When to see a doctor or ENT

Symptoms for longer than 3–4 weeks.
Fever, facial pain, thick green mucus lasting more than 10 days.
Blood in the mucus or a foul-smelling discharge from one side.
Hoarseness, trouble swallowing or weight loss.
Frequent sinus infections or reduced sense of smell.
No response to a trial of nasal spray and antihistamine.

Three common situations

Drip and cough every spring with sneezing and itchy eyes: likely allergic; a nasal steroid and antihistamine plan from your doctor helps.

Drip and morning hoarseness without nasal symptoms: consider reflux; review diet and see a doctor if it persists.

Thick mucus for weeks after a cold: use saline rinses, fluids and review at 3–4 weeks.

How to use a saline rinse safely

A saline rinse is one of the most useful tools for postnasal drip, but it must be done safely. Use distilled or sterile water, or tap water that has been boiled for at least a minute and cooled to lukewarm; never use untreated tap water, as rare but serious infections have been linked to it. Mix a premixed saline packet or the proportion recommended by the manufacturer, lean over a sink, tilt your head to the side and let the solution flow in one nostril and out the other, breathing through your mouth. Rinse once or twice daily during symptoms. Clean the device after every use, let it air dry, and replace it as advised.

Do dairy products or certain foods make mucus worse?

Many people feel that milk makes their phlegm thicker. Studies have not shown that dairy increases mucus production, although milk can leave a coating sensation in the mouth. Spicy food can make the nose run, and alcohol and caffeine can dehydrate, but there is no specific “mucus diet”. Focus on staying hydrated, treating allergies and avoiding irritants.

Key points to remember

Postnasal drip is common and treatable. Identify the trigger, use saline rinses and nasal steroids when appropriate, avoid constant throat clearing and see a doctor if it is long-lasting or comes with warning signs.

This guide is for general information and does not replace an assessment by your own doctor or ENT specialist.

Questions about postnasal drip

These answers are general information and do not replace an examination or individual medical advice.

What causes postnasal drip?

Allergies, colds, sinus infections, dry air, irritants, reflux and hormonal changes are the most common causes.

How can I stop postnasal drip at night?

Rinse the nose before bed, sleep with your head raised, humidify the room and treat any allergy.

Does postnasal drip cause a cough?

Yes. The mucus irritates the throat and triggers a cough, often worse lying down.

How long does it last?

After a cold, a few days to two weeks. With allergies it can last for the whole season.

Do I need antibiotics?

Rarely. Only for a confirmed bacterial sinus infection.

Is postnasal drip serious?

Usually not, but see a doctor if it persists for weeks or is associated with blood, fever, facial pain or weight loss.

Sources

This guide is for general information and does not replace medical advice. How a problem is diagnosed and treated depends on your examination and medical history. If you think you have an emergency, contact your local emergency services.