Cough

A cough is a powerful reflex that helps your body clear the airways of irritants, mucus, and germs, protecting your lungs from infection. While most coughs resolve on their own, understanding what triggers them and how to manage symptoms can bring relief and peace of mind.

Table of contents

• What is a cough?
• Types of cough
• Common causes of cough
• When to see a doctor
• Possible complications
• Home remedies and self-care
• Medical treatment options
• Prevention

What is a cough?

A cough is a sudden, forceful push of air from your lungs through your airways and out of your throat and mouth. It is your body’s natural way of responding when something irritates your throat or airways^[1]. You usually feel a tickly or scratchy feeling in your throat that triggers the urge to cough^[1].

Coughing is actually a protective reflex—an automatic response that helps keep you healthy. It clears mucus, dust, and other foreign substances from your respiratory tract, protecting your lungs from infection and inflammation^[7]. The cough can be either voluntary, meaning you do it on purpose, or involuntary, happening automatically when nerves in your airways are stimulated^[5].

A cough involves three phases. First, you take a deep breath in. Next, a part of your airway called the glottis (a lid-like structure over your windpipe) closes tightly, trapping air in your lungs. Then, your chest, abdomen, and diaphragm (the muscle below your lungs) contract forcefully, building up pressure. Finally, the glottis opens suddenly, and air rushes out at nearly the speed of sound, creating the characteristic coughing sound^[20].

Types of cough

Coughs can be classified in several ways based on their characteristics and duration.

Dry versus productive cough: You might have a dry, nonproductive cough that does not bring up mucus, or a wet, productive cough that produces mucus or phlegm (thick fluid from your lungs and airways)^[1][4]. When you have a productive cough, you cough up this phlegm from your lungs and lower airways^[4].

Duration-based classification: Healthcare providers classify coughs based on how long they last^[7]:

• Acute cough: Lasts less than three weeks. This is often caused by viral infections like the common cold or flu^[4].
• Subacute cough: Lasts three to eight weeks^[7].
• Chronic cough: Lasts more than eight weeks and may indicate an underlying health condition^[4][7].

Special characteristics: Some coughs have distinctive sounds. A barky cough may be a sign of croup, while a cough ending with a whooping sound suggests whooping cough^[1].

Common causes of cough

Many different conditions can trigger a cough. The most common causes depend on whether the cough is short-term or long-lasting.

Short-term cough causes: The most frequent cause of an acute cough is a viral infection in your upper respiratory tract, such as the common cold or flu^[4][7]. These viruses infect your nose, throat, and voice box, then often spread to your lungs. The infection causes inflammation or redness in your throat, windpipe, or lungs^[4]. In healthy people, this type of cough normally goes away on its own within two to three weeks^[4].

Other causes of short-term cough include^[1][4]:

• COVID-19
• Acute bronchitis
• Pneumonia
• Whooping cough (pertussis)
• Laryngitis (inflammation of the voice box)
• Sinusitis
• Poorly controlled asthma

Long-term cough causes: A persistent or chronic cough lasting more than eight weeks may be caused by several conditions^[1][4]:

• Asthma, sometimes called “cough-variant asthma”
• Acid reflux or GERD (gastroesophageal reflux disease), where stomach acid flows back into the throat
• Postnasal drip, where mucus drips down the throat from the back of the nose or sinuses
• Chronic obstructive pulmonary disease (COPD) and other chronic lung conditions
• Certain medications, particularly ACE inhibitors (used for high blood pressure) and some nasal sprays
• Smoking or vaping
• Allergies to pollen, pet dander, mold, or other substances
• Irritants like smoke, dust, and strong smells

Sometimes the cough reflex becomes sensitized after a viral infection, causing an ongoing cough to develop even after the infection has cleared^[4]. Less common causes of chronic cough include cancers affecting the lungs, heart disease, and vocal cord disorders^[1].

When to see a doctor

While most coughs clear up on their own within three to four weeks, certain symptoms warrant medical attention^[13].

You should talk to a healthcare provider if you or your child has^[1][4]:

• A cough lasting longer than three weeks or getting worse over time
• A cough that makes a barking or whooping sound
• Vomiting from coughing
• A fever lasting more than a few days
• Unexplained weight loss
• A weakened immune system (for example, from chemotherapy or diabetes)

Seek urgent medical help if you experience^[1][13]:

• A very severe cough or one that quickly gets worse
• Difficulty breathing or shortness of breath
• Chest pain
• Coughing up blood
• Feeling very unwell
• Swollen and painful neck glands

A cough lasting more than three weeks with no obvious cause should be evaluated by a doctor, as it may be a sign of a health problem requiring treatment^[4].

Possible complications

While coughing is usually helpful, excessive or forceful coughing can sometimes lead to complications.

Too much coughing can cause^[1][3]:

• Extreme tiredness and sleep disruption
• Headaches
• Dizziness or fainting
• Muscle pain and strains
• Rib fractures (in severe cases)
• Vomiting
• Urinary incontinence (leaking urine)
• Difficulty breathing
• Worsening of asthma symptoms

Chronic coughing can interrupt sleep, reduce concentration and work performance, and cause frustration and anxiety^[7]. It may also affect social interactions, especially when infectious diseases are a concern.

Home remedies and self-care

Many simple measures can help ease a cough and make you more comfortable while your body heals.

Stay hydrated: Drinking plenty of fluids is one of the most important steps. When you’re sick, mucus can trickle down the back of your nose. Staying hydrated thins this mucus, making it less likely to irritate your throat and trigger a cough^[9]. It also makes it easier for your lungs to clear out discharge^[9].

Try honey: Honey can soothe the scratchiness in the back of your throat. Research suggests that a spoonful of honey works just as well as some over-the-counter medications to calm a cough, particularly nighttime coughs^[1][9]. You can take a tablespoon of honey as needed or stir it into a warm drink like hot lemon and honey^[11][13]. Important: Never give honey to babies under one year old^[1].

Use steam and humidity: Sitting in a steamy shower or using a humidifier can help loosen mucus and keep your airways moist^[1]. Moist air from a vaporizer or humidifier may help relieve symptoms, though you should follow all cleaning instructions for these devices^[17].

Sip hot drinks: Research shows that hot beverages can ease cold symptoms, including cough. The liquids provide hydration, and the heat helps lower congestion^[9]. Try calming chamomile tea or ginger tea—ginger may help relax the smooth muscles in your airways^[9].

Elevate your head: If your cough is caused by a cold or allergies, try propping up your head with extra pillows at night. When you lie flat, mucus can pool and irritate your throat^[9][17].

Gargle with salt water: Gargling can soothe a sore throat and help loosen thick mucus. It may also help clear away allergens and bacteria. Dissolve half a teaspoon of salt in a glass of warm water, gargle, then spit it out^[9][17].

Avoid irritants: Don’t smoke or vape, as cigarette smoke and vaping mist can cause inflammation in your airways^[1]. Stay away from secondhand smoke, strong scents, dust, and allergens^[1][9]. If you have allergies, cleaning away mold, dust, and pollen from your home may help reduce coughing^[9].

Rest and stay home: Getting adequate rest helps your body heal. Try to stay at home and avoid contact with others if you have a high temperature or don’t feel well enough to do normal activities^[13].

Medical treatment options

If home remedies don’t provide enough relief, several over-the-counter and prescription options are available.

Over-the-counter medicines: Several types of cough medicines may help^[1]:

• Cough suppressants like dextromethorphan help calm the part of your brain that triggers coughing. Use these for a dry, hacking cough that keeps you awake, but don’t suppress a productive cough too much, as coughing helps clear mucus from your lungs^[1][17].
• Expectorants like guaifenesin help thin out mucus, making it easier to cough up what’s irritating your airways^[1][17].
• Decongestants may help if postnasal drip is causing or worsening your cough^[1].
• Cough drops, throat lozenges, and throat sprays may numb or soothe your throat for temporary relief from the tickly feeling^[1][17].

Important: Don’t give cough medications to children unless their healthcare provider says it’s okay^[1]. Read labels carefully to understand what ingredients you’re taking, and ask a pharmacist if you need help choosing the right product.

Treating underlying conditions: The best way to stop a cough is to treat its underlying cause. If an ongoing health condition is causing your cough, your healthcare provider might prescribe^[1]:

• Antibiotics for bacterial infections (though most coughs don’t require antibiotics^[13])
• Antihistamines or steroid nasal sprays for allergies
• Inhalers for asthma or COPD management
• Oral steroids for croup or flare-ups of asthma or COPD
• Proton pump inhibitors or H2 blockers for acid reflux

Your doctor may use a chest X-ray or lung function tests to help identify the cause of your cough^[1]. For chronic cough, additional tests like CT scans or examination with a scope might be needed^[8].

Prevention

While you can’t prevent all coughs, certain measures can reduce your risk of developing one.

Practice good hygiene: Cover your mouth and nose with a tissue when you cough or sneeze, and throw used tissues in the trash immediately. If you don’t have a tissue, cough or sneeze into your elbow, not your hands^[19]. This helps prevent spreading germs to others.

Wash your hands frequently with soap and water for at least 20 seconds, especially after coughing, sneezing, or blowing your nose. If soap and water aren’t available, use an alcohol-based hand sanitizer with at least 60% alcohol^[19].

Avoid sick people: Try to avoid close contact with people who are sick with respiratory infections^[19]. If you’re ill, distance yourself from others and stay home from work or school when possible to avoid spreading germs.

Maintain a healthy environment: Keep your home free of irritants. If you’re sensitive to perfumes and fragrances in laundry detergents and air fresheners, switch to unscented products^[9]. Use a properly maintained humidifier to keep air moist, especially in dry environments.

Don’t smoke: Avoid smoking and using tobacco or vaping products. Stay away from secondhand smoke and other air pollutants^[17]. Smoking can lead to chronic “smoker’s cough” and increase the risk of serious lung conditions.

Get vaccinated: Stay up to date with recommended vaccines, including those for flu, COVID-19, and pneumonia, to reduce your risk of respiratory infections that cause coughing.