Why Do I Keep on Coughing? Discover the Common Causes and Solutions

Ongoing coughing can be caused by a cold, allergies, asthma, or acid reflux. See a doctor if it lasts over three weeks or you cough up blood.

Duration

• Acute: under 3 weeks, usually a cold or flu.
• Subacute: 3 to 8 weeks.
• Chronic: over 8 weeks.

Common causes

• Colds, flu and post-viral cough.
• Allergies and postnasal drip.
• Asthma.
• Acid reflux (GERD).
• Smoking.
• ACE inhibitor medicines.
• Whooping cough.

Relief

Honey (for adults and children over 1), fluids, humidifier and lozenges.

See a doctor if

Cough lasts over 3 weeks, or you cough up blood, have fever, shortness of breath, wheezing or weight loss.

Emergency

Trouble breathing needs 911.

How cough works

Coughing is a protective reflex that clears the airways of mucus and irritants. Cough receptors in the throat, windpipe and lungs send signals to the brainstem, causing a deep breath, closure of the voice box and a sudden forceful release of air at speeds up to 80 kilometers per hour.

How long it lasts

• Acute cough: less than 3 weeks, most often from a cold or flu.
• Subacute: 3 to 8 weeks, which often follows a respiratory infection.
• Chronic: more than 8 weeks in adults (4 weeks in children).

After a cold the airways stay sensitive, and the cough often lingers 2 to 3 weeks.

Common causes

• Viral infections like the common cold, flu, COVID-19 and RSV.
• Postnasal drip from allergies or sinus infections.
• Asthma, including cough variant asthma, which presents with cough only.
• Gastroesophageal reflux disease (GERD).
• Smoking, vaping and air pollution.
• ACE inhibitor blood pressure drugs, which cause a dry cough in about 10% of users.
• Whooping cough (pertussis), with violent coughing fits and a whoop on inhaling.
• Chronic obstructive pulmonary disease (COPD) and chronic bronchitis.
• Pneumonia, tuberculosis and lung cancer.

Relief

• Honey, one to two teaspoons, shown in studies to soothe cough as well as or better than some medicines. Do not give honey to infants under 12 months because of botulism risk.
• Warm fluids, lozenges and humidified air.
• Dextromethorphan for dry cough and guaifenesin to loosen mucus. Avoid in children under 4 years.
• Treat the cause: allergy medicines for postnasal drip, acid reducers for reflux, inhalers for asthma.
• Quit smoking and avoid irritants.

See a doctor if

Cough lasts longer than 3 weeks, comes with fever for more than 3 days, wheezing, night sweats, unintended weight loss, coughing up blood or thick green mucus, or breathlessness. Chronic cough in smokers needs checking. Tests may include chest X-ray, lung function tests, and sputum tests.

Emergency

Call emergency services if there is severe trouble breathing, chest pain, blue lips or face, coughing up large amounts of blood, or choking.

Cough phases and causes

Acute cough lasts under 3 weeks, subacute 3 to 8 weeks and chronic more than 8 weeks. After a viral infection, a cough may linger for 3 to 8 weeks due to airway sensitivity. The most common causes of chronic cough in adults are upper airway cough syndrome (postnasal drip), asthma and acid reflux. ACE inhibitor blood pressure medicines cause dry cough in up to 20 percent of users. Smokers face chronic bronchitis. Whooping cough (pertussis) causes severe coughing fits and is preventable by vaccination. A chest X-ray, spirometry and a medication review help find causes. Honey soothes cough in adults and children over 1 year.

Based on data from the American College of Chest Physicians and the CDC