What is a Dry Cough: Common Causes & Home Remedies

A dry cough brings up none.

The difference between a dry cough and a chesty one matters, because they are handled differently: a cough that brings up mucus may be helped by a medicine that thins it, while cough medicines will not stop a dry cough.

A cough can also be described by how long it has lasted. Coughs from a cold, flu or sinus infection usually begin quickly and settle within a few weeks. A cough that goes on longer is investigated differently, because the list of possible causes changes.

It is also worth knowing that a cough can be dry even when the cause is nowhere near the lungs. Acid reflux, a blood pressure medicine and hay fever can all produce one.

Most coughs are caused by a cold or flu. Beyond that, here are the causes a doctor will consider. This list is not a diagnosis - it is what your symptoms will be checked against.

• Cold, flu and other viral infections - The most common cause. Includes COVID-19, sinus infection and acute bronchitis.
• Mucus dripping down the throat - Mucus running down the throat from the back of the nose, often with sinusitis. Decongestants are used to relieve it.
• Allergies such as hay fever — Allergies of the nose and sinuses. Often worse at times of day when airborne allergens are high, usually the morning.
• Asthma — Coughing is one of the main symptoms, usually with wheezing, breathlessness or a tight chest. Often worse at night and early in the morning.
• COPD (chronic bronchitis or emphysema) — A long-term lung condition, and one of the common causes of a cough that does not go away.
• Acid reflux — A cough that keeps coming back, often with heartburn or a sour taste. Worse after eating, when lying down and when bending over.
• Smoking and secondhand smoke — A common cause, and the one cause you can remove yourself.
• ACE inhibitor medicines — Blood pressure and heart medicines in this group can cause a dry cough that does not go away. ARB medicines do this less often.
• Whooping cough — Coughing bouts lasting a few minutes, worse at night, sometimes with a "whoop" sound between coughs. The cough can last weeks or months.
• Chest infection — Usually a chesty cough that brings up green or yellow mucus, not a dry one. The cough and mucus can last up to 3 weeks.
• Tuberculosis — A cough lasting weeks, sometimes bringing up blood, often with fever, night sweats or weight loss.
• Throat and airway disorders — Another group of causes. Croup, for example, mainly affects young children.
• Lung cancer and other lung diseases — A cough is rarely a sign of lung cancer, but it is one reason a long cough gets checked. Bronchiectasis and similar conditions also cause cough.
• Heart failure — A cough that gets worse when you lie down, often with swelling in your legs, especially if you already have heart disease.

In some people, no specific cause is found even after a full assessment. That happens, and it does not mean the cough is not real.

Most coughs settle on their own. A cough usually clears up without treatment within 3 to 4 weeks.

Published definitions do not all draw the line in the same place, so it helps to know what the numbers refer to:

• One widely used clinical classification calls a cough acute (short-lived) if it clears within about 3 weeks, subacute if it lasts 3 to 8 weeks, and chronic (long-lasting) if it lasts longer than 8 weeks.
• Another commonly used classification calls coughs acute up to 2 to 3 weeks, and chronic beyond 2 to 3 weeks.
• Practical advice converges near the same point: a cough still going after about 3 weeks is the trigger to get it looked at, not to keep treating it at home.

Those are definitions, not competing advice, and the action they point to is the same. Three weeks is roughly where a cough stops being routine.

See a doctor if a cough lasts longer than 3 weeks. That is the threshold used by UK guidance, and it applies even if you feel otherwise well.

See a doctor sooner, without waiting the three weeks, if you have any of these:

• unexplained weight loss
• a weakened immune system — for example because of chemotherapy or diabetes
• a cough that has lasted longer than 10 to 14 days
• fever
• night sweats
• a cough that brings up blood
• swollen and painful glands in the side of the neck
• a cough that gets worse when you lie down, or swelling in your legs, especially if you have heart disease
• a high-pitched sound when you breathe in (called stridor)
• thick, foul-smelling, yellowish-green phlegm
• a violent cough that began suddenly
• a cough in an infant under 3 months old

The 3-week and 10-to-14-day triggers come from different sets of guidance, and they are not contradictory: the shorter one just gets a cough looked at sooner.

At the appointment, your doctor will usually listen to your chest, and may take a sample of any mucus you are coughing up. Depending on what they find, they may order an X-ray, an allergy test or a test of how well your lungs work. Referral to a hospital specialist is rare.

Tuberculosis is one of the conditions a doctor will consider.

That is not alarmism — it is the reason this section exists. India accounts for about a quarter of the world's new tuberculosis cases, the largest share of any country. A cough that will not settle needs to be assessed here, not assumed to be a lingering cold.

Tuberculosis (TB) is an infectious disease caused by bacteria that most often affects the lungs. It spreads through the air when a person with TB disease coughs, sneezes or spits. It is not spread by touching, kissing, or sharing food or dishes.

The common symptoms of TB are:

• a prolonged cough, sometimes with blood
• chest pain
• weakness and fatigue
• weight loss
• fever
• night sweats

Seek medical attention if you have symptoms such as a prolonged cough, fever and unexplained weight loss. Early treatment for TB helps stop the spread of the disease and improves your chances of recovery.

Two things are worth saying plainly, because they are the reason not to put this off:

• TB disease can almost always be cured with antibiotics. Untreated, or treated improperly, it can be fatal.
• Not everyone who is infected gets sick. Inactive (latent) TB causes no symptoms and cannot be spread to others, but it can become active later - which is why a doctor may test you even if you feel well.

See a doctor promptly rather than waiting it out if:

• you have been in contact with someone who has tuberculosis
• you have unintentional weight loss or night sweats

Getting screened also matters if something is working against your immune system. Diabetes, a weakened immune system, undernutrition, tobacco use and heavy alcohol use all raise the risk of TB disease.

Home remedies can ease a dry cough, but they do not treat its cause. If your cough has lasted more than three weeks, a remedy is not the answer - an assessment is.

Things you can try:

• Rest, and drink plenty of fluids. Water helps ease a cough whether you drink it or add it to the air.
• Use a vaporizer, or take a steamy shower, to add moisture to the air and soothe a dry throat. If you use a humidifier, clean and maintain it properly.
• Suck a cough drop or a hard candy for a dry, tickling cough. Never give these to a child under 3 - they can cause choking.
• Try a hot lemon and honey drink. It can have an effect similar to cough syrup.
• Stay at home and away from other people if you have a high temperature or do not feel well enough for your normal activities.
• Do not smoke, and stay away from secondhand smoke.
• Paracetamol or ibuprofen can ease pain. Check the leaflet first, and ask a pharmacist if you are not sure whether it suits you or your child - ibuprofen is not suitable for everyone, and in some people with asthma it can trigger symptoms. Keep in mind that anti-inflammatory painkillers like ibuprofen can also cause or worsen heartburn and reflux, so if your cough comes from reflux, ask a pharmacist first.

How to make a hot lemon and honey drink

1. Squeeze half a lemon into a mug of boiled water.
2. Add 1 to 2 teaspoons of honey.
3. Drink it while it is still warm.

Do not give hot drinks to small children, and never give honey to a baby under 1 year old.

If your cough is coming from reflux or allergies

A cough that keeps coming back, along with heartburn or a sour taste in the mouth, often points to acid reflux. Simple changes can reduce it:

• Eat smaller, more frequent meals.
• Lose weight if you are overweight.
• Avoid the food and drink that triggers your symptoms - common ones are coffee, tomatoes, alcohol, chocolate and fatty or spicy foods.
• Do not eat within 3 to 4 hours before bed.
• Do not wear clothes that are tight around the waist.
• Raise the head of your bed by about 10 to 20 cm, using wood, bricks or books, so your chest and head are above your waist. Do not try to get the same effect with extra pillows — that increases pressure on your belly and can make symptoms worse.

If your cough tracks with the pollen season, it may be an allergy:

• Stay indoors when airborne allergens are high, which is usually in the morning.
• Keep windows closed and use an air conditioner.
• Do not use fans that draw in air from outdoors.
• Shower and change your clothes after being outside.
• If your allergies last all year, use dust mite covers on your pillows and mattress, use an air purifier, and avoid pets with fur.

If you have asthma or another long-term lung condition, keep taking the medicines your doctor has prescribed, and follow your asthma action plan.

An honest note about home remedies

There is limited evidence that hot lemon and honey, and herbal medicines, actually help ease a cough. They are worth trying because they are gentle and may soothe your throat, but they ease symptoms, not the cause. The job of a home remedy is to get you through the days while your body recovers - not to postpone a doctor's visit.

You can ask a pharmacist about cough syrup, cough medicine and cough sweets. Be clear about what they do: they will not stop your cough, but they may help you cough less.

Two groups of products are worth knowing about, because they are used for different jobs:

• Expectorants such as guaifenesin are for a chesty cough. They work by thinning the mucus in your airways so that it is easier to cough up. Guaifenesin may help control symptoms, but it does not treat the cause of your symptoms or speed up recovery. It is not a treatment for a dry cough. If your symptoms do not improve within 7 days, or you also have a high fever, a rash, or a headache that does not go away, see a doctor.
• Decongestants help clear a runny nose and relieve postnasal drip, which is useful when mucus dripping down your throat is setting off the cough. Check with a doctor before taking a decongestant if you have high blood pressure.

A few more things worth knowing before you buy anything:

• Decongestants and cough medicines containing codeine fall into this group.
• For a cough that comes with a cold or flu, antihistamines may work better than non-prescription cough medicines. Ask a pharmacist which product suits your symptoms.
• Some cough medicines should not be given to children under 12 years old.
• A herbal medicine called pelargonium is used for a cough and is suitable for people aged 12 and over. Ask a pharmacist whether it is right for you.
• Some medicines and herbal treatments are not suitable for everyone — for example, if you are pregnant. Always check the leaflet or speak to a pharmacist before taking them.
• Check the label carefully before using two or more cough and cold products at the same time. They may contain the same active ingredient, and taking them together could give you an overdose. This matters most when you are giving them to a child.

On antibiotics: they are not normally prescribed for coughs. A doctor will only prescribe them if you need them — for example, if you have a bacterial infection or you are at risk of complications. A dry cough from a cold or flu is not one of those situations.

The age limit depends on the product. There is no single rule, and mixing the numbers up is how children get the wrong medicine.

• Honey — Babies under 1 year
• Cough drops or hard candy, for a dry tickling cough — Children under 3 years — choking risk
• Non-prescription cough and cold combination products, including those containing guaifenesin — Children under 4 years — these products can cause serious side effects or death in young children
• Any over-the-counter cough medicine — Not suitable for children under 6 years. For a child of 6 or younger, ask the child's doctor first, even if the label says it is for children
• Some cough medicines — Children under 12 years
• Pelargonium, a herbal medicine (not always available in India) — Children under 12 years

For children aged 4 to 11, use caution and follow the package directions carefully. Never give a product made for adults to a child. Over-the-counter cough medicines are likely not to work in young children. They can cause serious side effects, and the combination products can cause death in young children. That is why the doctor's advice comes first.

If you are measuring a liquid, use the measuring spoon or cup that came with the medicine, not a household spoon.

Call 112, India's emergency number, straight away — and ask for an ambulance on 108 if you need one — if you have any of these:

• shortness of breath or difficulty breathing
• hives, or a swollen face or throat with difficulty swallowing
• coughing up blood
• chest pain
• a cough that is very bad or quickly getting worse — a hacking cough, or a cough you cannot stop
• you feel very unwell

If you have asthma and your reliever inhaler is not helping, or your symptoms get worse, get emergency help rather than waiting. Do not drive yourself to hospital.