What is a cough?

Coughing is a protective reflex. It can remove dust and other things that have been breathed in. A cough can also get rid of mucus from your throat and chest. Coughing is how your body cleans the lungs and airways.

What symptoms are related to a cough?

The symptoms that come with a cough will vary. It depends on what is causing your cough.

You can have a productive (chesty) or non-productive (dry) cough.

A non-productive cough does not have any mucus or phlegm.

A productive or wet cough is a type of cough that makes mucus. It may cause a feeling of congestion or tightness in your chest.

When you have a productive cough, you cough up mucus. This is known as phlegm (the word sounds like 'flem'). The phlegm comes up from your lungs and lower airways.

A productive cough is not necessarily a sign of a more serious illness. You may not need antibiotics or other treatments. However, a productive cough can sometimes indicate a serious problem like pneumonia or heart failure.

Coughing that lasts for more than 3 weeks may also be a sign of a health problem. See your doctor if there is no other reason for your cough.

What causes a cough?

There are many different causes for a cough.

Short-term cough (less than 3 weeks)

The most common cause of a short-term (acute) cough is a viral infection.

Viruses can infect your nose, nasal passages, mouth, throat and voice box. This area of your body is called the 'upper respiratory tract'. These viruses often then spread to your lungs.

The common cold and flu viruses cause infections in the upper respiratory tract. The infection causes inflammation or redness in your throat, windpipe (trachea) or lungs.

In healthy people, this type of cough normally goes away on its own within 2 to 3 weeks.

Other causes of short-term cough (lasting less than 3 weeks) can be:

• COVID-19
• laryngitis — an inflammation of your larynx (voice box) from infection, overuse or irritation
• sinusitis
• whooping cough (pertussis)
• infections in the airways and lungs, such as bronchitis and pneumonia
• asthma that is not well controlled

Persistent cough

A persistent cough (lasting more than 8 weeks) is also known as a 'chronic cough'. It may be caused by a health issue. Sometimes the cough reflex may become sensitised. This can cause an ongoing cough to develop.

Some of the common respiratory causes of persistent cough are:

• Post-viral cough — following a viral respiratory tract infection.
• Asthma — this may be called 'cough-variant asthma'.
• Ongoing sinusitis or post-nasal drip (also called upper airway cough syndrome) — mucus drips down the throat. The mucus comes from the back of the nose or sinuses.
• Habit cough (now known as 'somatic cough syndrome') — there is no underlying disease that causes the cough. Habit cough occurs most commonly in children. It goes away when the child is asleep.
• Chronic obstructive pulmonary disease (COPD) — ongoing blockage of the airflow in the lungs that interferes with breathing.
• Infections such as whooping cough (pertussis).

Cough can also be caused by:

• Lung cancer or cancer of the larynx.
• Bronchiectasis — where the airways are damaged. You can't clear mucus properly, which leads to chest infections. It can cause a productive cough ('phlegm cough').
• Tuberculosis and other chronic infections.
• Cystic fibrosis — a genetic condition that affects your lungs.
• Silicosis — a long-term lung disease that is caused by breathing in silica dust.

Other causes of cough include:

• Reflux (GORD) — this happens when stomach acid comes up into the windpipe. It can cause irritation.
• Obstructive sleep apnoea — a common sleep disorder which causes snoring and stop-start breathing during sleep.
• Some medicines — such as ACE inhibitors. Talk with your doctor about this as alternative medicines may be available that do not cause a cough.
• Heart failure — a condition where your heart muscle is weak and can't pump blood around your body properly.

When should I see my doctor?

You should seek medical care if you:

• have a cough that lasts for more than 3 weeks
• are short of breath or have chest pain or unexplained tiredness
• cough up blood, mucus, or phlegm
• have trouble sleeping because of coughing
• have unexplained problems like weight loss or a fever

If your child has a cough, see a doctor if they have:

• a cough that starts suddenly — it may be due to breathing in a small object
• a cough that lasts longer than 2 weeks, with or without a cold
• a cough that interferes a lot with their sleep or daily life
• trouble breathing
• a high fever
• sleepiness and tiredness, and they seem unwell
• fewer wet nappies than usual or are not drinking much

When to seek urgent care

Call triple zero (000) for an ambulance if your child:

• has a change in skin colour, turning blue or very pale
• is having trouble breathing
• is drowsy or does not respond
• is choking

How is a cough treated?

Treatment for a cough depends on the cause.

Your doctor will want to treat any underlying health issue that is causing a long-term (persistent) cough. There may be triggers or activities that make the symptoms of a persistent cough worse. These should be avoided.

Self-management

There are some things you can do to relieve the symptoms of cough:

• Stay well hydrated — it's important to drink plenty of water. If you have an existing health condition, check with your doctor about how much water is right for you.
• Rest and avoid vigorous activity until symptoms go away.
• Have some honey — it may help to reduce the severity and length of time you have the cough. One to 2 teaspoons of honey taken 30 minutes before bedtime may be helpful. It has been shown to help children with cough. But honey should never be given to children aged under 12 months.

Cough medicines

There are many cough remedies and over-the-counter medicines for cough. They are not generally helpful in treating short-term cough. They may have side effects.

Cough medicines may be harmful to young children. The Australian Therapeutic Goods Administration (TGA) says that cough and cold medicines should NOT be given to children younger than 6 years. Examples of these medicines are:

• cough suppressants
• antihistamines
• decongestants

There is not much evidence that these medicines are helpful for a cough.

Older children aged 6 to 11 years can be given cough and cold medicines. BUT children should only be given these medicines if advised by a health practitioner. This could be a doctor, pharmacist or nurse practitioner.

Antibiotics

Most short-term coughs are due to viral infections of the upper respiratory tract. These coughs usually go away on their own.

Antibiotics do not help viral infections because they don't kill viruses. Antibiotics may do harm in these circumstances.

Other remedies

There are many common cold and cough remedies that do not work. They do not have good scientific evidence to support their use.

Examples of these are vitamin C, salt therapy, steam inhalation and humidifiers.

Honey has been shown to be helpful for children (over 12 months) with cough.

Smoking

Smoking or breathing other people's smoke can make cough symptoms worse. Try to avoid being around people who are smoking.

If you are a smoker, try to cut down or quit. For advice on quitting smoking, visit the Quit Now website.

How can I prevent a cough?

You can't prevent a cough caused by cold, flu or COVID-19. However, you can lower your chances of getting sick in the first place.

Self-care

Wearing a face mask is likely to reduce your risk of catching a respiratory virus. You may want to wear a mask when you're in a high-risk setting such as:

• in crowded areas
• on public transport
• waiting to see your doctor

Good ventilation and cleaning (filtration) the air in a room can help to reduce the risk of spreading a virus.

At home, you can open doors and windows to allow a good flow of air. You may also want to use an air purifier to reduce the risk of other people catching the virus.

You can help stop the spread of respiratory viruses by:

• staying away from people who are coughing or sneezing
• coughing or sneezing into a tissue
• using good hand hygiene (wash your hands often)
• staying home when sick

Vaccination

Adults and children can get vaccinated against some bacterial infections that cause coughing. Vaccines are available against the bacteria that cause whooping cough (pertussis) and pneumococcal disease.

You can also get vaccinated against COVID-19 and influenza.

Keep your children up to date with their vaccines. Adults should also talk to their doctor about vaccines.

Medicines

If you think a cough is caused by a side effect of a medicine, see your doctor. A different medicine may be available.

If a cough is caused by asthma, correct asthma treatment can help.

Smoking

Tobacco smoke is a significant trigger for cough. Avoid cigarette smoke. Things in the environment and workplace can also cause asthma-related coughs.

Pollen

Stay indoors if there is a high pollen count in the environment.

Complications of a cough

An ongoing or intense cough can cause complications. These include:

• sleep disruption
• headache
• hoarseness and laryngitis
• urinary incontinence
• back and chest pain
• fractured rib

Resources and support

You can call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.