Chronic Cough or 100-day Cough?

Persistent cough isn’t just annoying – it can significantly impact your quality of life. Learn more about what causes chronic cough, when to be concerned, and how to find relief.

Are you troubled by a cough that just won’t go away? Many people experience persistent coughs, but when does it become a concern? To help clarify this issue, Dr Jessica Tan, Head and Senior Consultant at the Department of Respiratory Medicine, Sengkang General Hospital, covers the issues surrounding chronic cough, its causes, and how to manage it effectively.

What is Chronic Cough?

Dr Tan defines chronic cough as a cough that lasts longer than eight weeks for adults and four weeks for children. "If the cough lingers beyond these timeframes, it’s time to seek medical advice," she advises.

Certain symptoms should raise red flags. Dr Tan emphasises, "If one experiences coughing up blood, prolonged fever, chest pain, shortness of breath, or unexplained weight loss, they should see a doctor right away." These could indicate more serious health issues.

Since the COVID-19 pandemic, SKH has seen a significant increase in patients with chronic coughs. Dr Tan estimates that there has been a 25-30% increase in cases compared to before the pandemic. "This rise reflects greater awareness about respiratory symptoms, with many concerned about lingering effects from COVID-19 or other respiratory illnesses."

Common Causes

Dr Tan identifies several common causes of chronic cough:

Asthma: This condition causes airway inflammation and leads to cough, shortness of breath and increased mucus production.
Chronic Obstructive Pulmonary Disease (COPD): Often linked to smoking, COPD causes persistent breathing issues.
Post-Nasal Drip/Allergic Rhinitis: Excess mucus from the inflamed nasal passages can ‘drip’ down the back of the throat and trigger a cough reflex.
Gastroesophageal Reflux Disease (GERD): Acid from the stomach may reach the throat and airways, irritating the throat and cause coughing.

"Understanding these causes is crucial," Dr Tan emphasises. "They all affect how the body responds and can lead to a persistent cough."

What is the ‘100-day Cough’?

You may have heard about the so-called ‘100-day cough’. Dr Tan explains that this term originally referred to whooping cough (pertussis), which historically caused prolonged coughing spells lasting several weeks to months.

"Thanks to childhood vaccinations, most younger people are now protected from this bacterial infection,” she notes but adds, “While older generations might consider it normal for a cough to last so long, it is important to remember that not all chronic coughs will resolve on their own if left unevaluated and untreated.”

When to Seek Help

If the cough lasts more than eight weeks, it is time to consult a doctor. "Start with a general practitioner (GP)," advises Dr Tan. "Your GP can do initial evaluation of your condition and refer you to a specialist, if necessary."

To determine the cause of a chronic cough, doctors may perform several tests. These include medical history and physical exams which is essential in understanding the patient’s symptoms and health history.

A chest X-ray is essential to help identify issues like pneumonia. Pulmonary function tests assess lung function and can help diagnose asthma or COPD, while the sputum culture test helps to exclude infections such as tuberculosis. In specific cases, a CT scan which is an imaging test helps identify more complex conditions, such as bronchiectasis or other chronic lung diseases. Dr Tan notes that these tests are vital for pinpointing the exact cause of the cough.

Treatment

Treating chronic cough depends on its underlying cause. Dr Tan explains that effective treatment often includes nasal decongestants for allergic rhinitis, inhaled corticosteroids for asthma or medications to suppress gastric acid for GERD, as well as lifestyle changes like quitting smoking and avoiding irritants.

For those dealing with a persistent cough, Dr Tan advises patients to stay hydrated as drinking plenty of fluids can help thin mucus. Staying away from irritants like smoke, strong odours and allergens may help improve their symptoms. If post-nasal drip is an issue, propping oneself up can help reduce coughing at night.

Maintaining a healthy lifestyle by exercising regularly and eating a balanced diet will support overall health. Over-the-counter remedies like cough drops or syrups may provide temporary relief. "Taking these steps can make a significant difference in managing symptoms," Dr Tan concludes.

Chronic cough is more than just an annoyance; it can signal underlying health issues that need attention. By understanding its causes and knowing when to seek help, you can take control of your respiratory health!

Main Types of Cough Medicines

Cough suppressants (e.g. codeine, promethazine, dextromethorphan)

These suppress the urge to cough and are mainly used to treat dry coughs. Cough medicines containing codeine may be addictive – always consult a doctor or pharmacist before using any cough medicine.

Expectorants (e.g. guaifenesin, ivy leaf extract)

Expectorants help with wet (productive) coughs by thinning the phlegm and making it easier to be coughed out. Expectorants should be avoided for dry cough as they may worsen it.

Mucolytics (e.g. acetylcysteine)

Similarly, mucolytics help to thin the phlegm in wet coughs so it is easier to cough out. They work by breaking down the chemical bonds in mucus.

Reminder: Over-the-counter cough medicines should only be used for short-term relief of symptoms as chronic coughs (lasting longer than eight weeks) tend to have underlying causes which should be assessed by a doctor.

​Chronic Cough or 100-day Cough?