Chronic cough is among the few medical complaints that habitually prompt a visit to the doctor’s office.  Understandably so, since it affects approximately 10% of the global population ¹. 

A cough serves a purpose, as a natural reflex helping to get rid of external irritants finding their way into our respiratory systems. However, an unrelenting cough is an uncomfortable situation. For the most part, coughs subside on their own; either within a short time when you expel the irritant or following the course of a bout of infection.

However, when your cough persists it can be an indication of some other concern requiring further attention.

A chronic cough is described as one lasting for eight weeks or longer. Most chronic coughs can be assigned to a specific underlying cause. Unfortunately, anywhere between 5-10% cases might not have a specific cause for their coughs ². These cases of chronic cough are referred to as idiopathic chronic cough.

This article will highlight possible causes for your chronic cough and ways to manage and prevent a persistent cough.

What Are the Causes of My Chronic Cough?

It is relatively natural to assume the cause of a chronic cough is previously interacting with an infectious source. However, infections are actually a rare cause of a nagging chronic cough.

The most common causes for chronic coughs are gastroesophageal reflux disorder (GERD), asthma, and a post-nasal drip (also called upper airway cough syndrome)  ³, or a combination of the three.

Post-Nasal Drip

A post-nasal drip occurs when excessive mucus collects and drips into the back of your throat. This can be relatively normal, especially during allergy season. However, when the mucus flow is continuous, it can irritate the larynx and sensitive cough centers, resulting in a chronic cough. Allergic rhinitis and chronic sinusitis have been noted as the most common causes of a post-nasal drip ⁴.

Asthma

Another likely source to watch out for, as a chronic cougher, is asthma. Often the only sign of underlying asthma is a cough. It is possible to neglect the rarer signs of asthma, such as wheezing and difficulty breathing, since you are primarily experiencing a nagging cough. Cough variant asthma can progress to classic asthma in  30–40% of adults ⁵.

GERD

As high as 25% of the cases of chronic cough can probably be attributed to gastroesophageal reflux disorder (GERD) ⁶. Classically, GERD presents with a burning sensation in the chest along with frequent belching. However, in certain instances, coughing might be the only sign of underlying GERD. 

COPD

Lung conditions such as chronic obstructive pulmonary disease (COPD) ⁷ and chronic bronchitis also present with a cough as the primary sign. Due to the deterioration in the condition of the lungs, it is common to notice excessive coughing as a way to remove the mucus buildup within the respiratory tract.

Drug-Induced Cough

An unlikely, and frequently neglected, source of a chronic cough is the medications that we take ⁸. A common type of drug associated with a dry chronic cough are the anti-hypertensive drug angiotensin-converting enzyme inhibitors (ACEIs) ⁹. Other medications which can result in a cough as an adverse effect include heart medicines that block calcium channels, proton pump inhibitors such as omeprazole, antiepileptics including phenytoin, and anti-rheumatic drugs like methotrexate.

This list of causes of a productive cough is not exhaustive. Infections, bronchiolitis, bronchiectasis, cystic fibrosis, heart failure, and cancer are a few causes of chronic cough not on this list. However, the aforementioned causes make up the majority of the cases along with idiopathic chronic cough.

What Are Symptoms I Should Look Out For?

Once your cough has lasted beyond eight weeks, it is categorized as a chronic cough. Along with your cough, you may note other signs that can hint toward a likely cause for it. 

Taking note of which times during the day you notice significant coughing can provide essential clues. 

For example, the timings of the coughing fits are important in the case of GERD coughs. When you have a recurring cough while going to sleep it can be an indication of underlying acid reflux. Additionally, reflux chronic coughing is frequently associated with lying down. You may also observe frequent belching, an unusual taste in your mouth, and chest discomfort.

Chronic coughing that appears with the turn of the season should be promptly investigated for an asthmatic variant or allergic cough. Temperature changes can also increase cough sensitivity ¹⁰. Allergies can also result in a post-nasal drip cough. Along with a cough these conditions can also result in a runny nose, struggles with taking deep breaths, and hoarseness due to continuous laryngeal (voice box) irritation.

For many, coughing can cause other symptoms. These include soreness in the throat, muscular pain in the chest, difficulty sleeping, and anxiety. Due to pressure changes noted with coughing, it is not uncommon to observe leaking of urine as well. Women frequently report this symptom and are among the first to seek medical help for a chronic cough due to its additional effects ¹¹.

With a cough, it is also important to record any severe symptoms. Coughing blood, weight loss, high fever, and significant chest pain are all indications of a chronic cough that has a more serious cause. Cancer, tuberculosis, and heart conditions are a few on this list.

It is important to track all your additional symptoms concerning your chronic cough. When you visit your healthcare provider they give clues indicating your diagnosis and in turn your cough treatment.

How Is a Chronic Cough Diagnosed?

Most coughs subside on their own after a while. In the case of infections, coughs might be one of the last signs to fade away. Opting for simple home remedies, such as warm fluids, steam, and over-the-counter antitussives, can help tackle a lingering cough.

When a cough has lasted beyond two to three weeks and is deteriorating your quality of life, consider checking in with your healthcare provider.

During your visit with your doctor, you should try and detail all the symptoms you have noticed alongside your cough. This should also include the type of cough you had, which could be either dry or productive. Additionally, highlight any changes in the frequency, such as coughs that occur at night or might appear with the changes in season. Certain activities include lying down, or exercising ¹² can also provoke coughing.

Following a detailed history, your doctor is likely to conduct some tests to narrow down a possible cause for the cough. Some of these tests include:

• Standard oxygen pulse oximetry
• Spirometry
• Pulmonary challenge tests
• Functional lung capacity testing
• Tests for sensitivity to allergens
• Sputum culture
• Fractional Exhalation of Nitric Oxide (FeNO) test
• Plethysmography
• Chest X-ray
• Chest computed tomography (CT scan)
• Positron emission tomography (PET scan)
• Chest ultrasound
• Bronchoscopy
• Angiogram of the pulmonary vessels

Not every chronic cough will go through all these tests. The type of further testing is ideally based on the results of preliminary tests such as a pulmonary challenge test, lung capacity results, and a chest X-ray.

How Will My Chronic Cough Be Treated?

Treatment of a chronic cough frequently involves managing the underlying condition.

A trial of proton pump inhibitors (PPI) such as pantoprazole or rabeprazole can help manage chronic cough caused by GERD. Other medications can include antacids and histamine receptor blockers. Frequently a reduction in cough after a trial of PPIs indicates that the likely source of the cough was underlying gastric reflux.

Similarly, managing asthma or a post-nasal drip with standard medications to treat these conditions can help relieve a chronic cough. Along with medicines, people who have either of these as sources of their cough should also consider environmental triggers such as changes in weather, pollutants, or allergens, and try to avoid them.

Infectious coughs respond well to antibiotics if the infection is caused by bacteria, or antifungal medication if it is caused by a fungus. There is no standard medical treatment for coughs caused by viral infections. People with conditions like COPD, which typically presents with a chronic cough among other symptoms, can note exacerbations in the frequency of the coughs due to infection within the diseased lungs. These conditions may also benefit from a course of antibiotics if the infection is bacterial. Additionally, steroids, bronchodilators, oxygen, and pulmonary rehabilitation are standard therapy considerations for COPD. 

When standard cough medications do not work, doctors may consider medications that alter cough sensitivity. Gabapentin is one such drug that has proven to be safe and effective in improving cough frequency for chronic coughers ¹³. 

It is vital to remember that a significant portion of chronic coughs have no underlying cause. Most of these chronic coughers have tried a long list of methods to suppress their cough. For them, behavioral cough suppression therapy (BCST) has been proven to provide some benefits ¹⁴. BCST is carried out by a speech pathologist. Chronic coughers are taught how to suppress their urge to cough and are over time able to observe significant control over their coughs.

What Are the Complications of Having a Chronic Cough?

Most of the complications, or rather effects, of having a chronic cough are related to a deterioration in the general quality of life. 

For one, chronic coughers are unable to participate in their regular activities. This can lead to a disruption in their work and social life. Additionally, coughing continuously can also affect your sleep quality.

Coughing bouts can cause chest pain and muscular aches. Additionally, forceful bouts can also cause vomiting. Rarely, prolonged bouts of cough can result in dizziness or syncope.

As mentioned earlier in the article, the forceful nature of coughing can also result in a loss of bladder control.  Chronic coughing can also result in hernias, such as intercostal ¹⁵, inguinal and femoral hernias. This is because the long duration under which muscles are exposed to the aggressive nature of a cough can result in their weakening.

A rare complication of chronic forceful coughing is fracturing a rib. Studies have noted rib fractures are more common among elderly women, who pose a high-risk group for developing bone fractures in general ¹⁶.

Among children, a potential complication of chronic coughing is subconjunctival hemorrhage ¹⁷. This is when the blood vessels within the conjunctiva (the membrane on the inside of the eyelids and over the eye) rupture due to the forceful nature of a cough. This results in the whites of the eyes turning blood red. While this often seems quite worrisome at first glance, treating the underlying cause of the cough assists with a resolution of the hemorrhage as well.

How Can I Prevent a Chronic Cough?

One of the foremost ways to tackle a cough is to treat the underlying cause. To do so, tracking your cough and associated symptoms can help your healthcare provider with creating the optimal treatment plan for you.

For chronic coughers, understanding possible triggers for a cough can also be crucial. Continuous exposure to a trigger can result in a chronic cough. Allergens or changes in season and humidity are all known factors that can affect cough sensitivity. Additionally, being mindful of your exposure to pollutants, both indoor and outdoor, can significantly change your cough frequency ¹⁸.

For those prone to acid reflux, timing your meals and opting for smaller meals can provide significant relief. Avoid consuming meals at least three hours before your bedtime.

The harmful products of cigarette smoking are known irritants to the respiratory system. Additionally, studies have shown that the chances of developing COPD increase as high as 50% among those who smoke ¹⁹. Quitting smoking not only reduces cough frequency but also assists your lungs to repair some of the damage likely caused.

A primary way to manage chronic cough is to have it looked at early. Starting treatment early also helps to lessen the duration that chronic coughs last. For treatment strategies that take time, such as behavioral cough suppression therapy, early diagnosis is the key.

References

1. Arinze, J. T., de Roos, E. W., Karimi, L., Verhamme, K., Stricker, B. H., & Brusselle, G. G. (2020). Prevalence and incidence of, and risk factors for chronic cough in the adult population: the Rotterdam Study. ERJ open research, 6(2), 00300-2019. https://doi.org/10.1183/23120541.00300-2019[↩]
2. Gibson, P., Wang, G., McGarvey, L., Vertigan, A. E., Altman, K. W., Birring, S. S., ... & Wiener, R. S. (2016). Treatment of unexplained chronic cough: CHEST guideline and expert panel report. Chest, 149(1), 27-44. https://doi.org/10.1378%2Fchest.15-1496[↩]
3. D'Urzo, A., & Jugovic, P. (2002). Chronic cough. Three most common causes. Canadian family physician Medecin de Famille Canadien, 48, 1311–1316. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2214091/[↩]
4. Nakajima, T., Nagano, T., & Nishimura, Y. (2021). Retrospective Study of the Effects of Post-nasal Drip Symptoms on Cough Duration. In vivo (Athens, Greece), 35(3), 1799–1803. https://doi.org/10.21873/invivo.12440[↩]
5. Niimi A. (2011). Cough and Asthma. Current respiratory medicine reviews, 7(1), 47–54. https://doi.org/10.2174/157339811794109327[↩]
6. Madanick R. D. (2013). Management of GERD-Related Chronic Cough. Gastroenterology & hepatology, 9(5), 311–313. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3740808/[↩]
7. Smith, J., & Woodcock, A. (2006). Cough and its importance in COPD. International journal of chronic obstructive pulmonary disease, 1(3), 305–314. https://doi.org/10.2147/copd.2006.1.3.305[↩]
8. Shim, J. S., Song, W. J., & Morice, A. H. (2020). Drug-Induced Cough. Physiological Research, 69 (Suppl 1), S81–S92. https://doi.org/10.33549/physiolres.934406[↩]
9. Yılmaz İ. (2019). Angiotensin-Converting Enzyme Inhibitors Induce Cough. Turkish thoracic journal, 20(1), 36–42. https://doi.org/10.5152/TurkThoracJ.2018.18014[↩]
10. Turmel, J., Bougault, V., & Boulet, L. P. (2012). Seasonal variations of cough reflex sensitivity in elite athletes training in cold air environments. Cough (London, England), 8(1), 2. https://doi.org/10.1186/1745-9974-8-2[↩]
11. Dicpinigaitis P. V. (2021). Prevalence of stress urinary incontinence in women presenting for evaluation of chronic cough. ERJ open research, 7(1), 00012-2021. https://doi.org/10.1183/23120541.00012-2021[↩]
12. Boulet, L. P., Turmel, J., Irwin, R. S., & CHEST Expert Cough Panel (2017). Cough in the Athlete: CHEST Guideline and Expert Panel Report. Chest, 151(2), 441–454. https://doi.org/10.1016/j.chest.2016.10.054[↩]
13. Shi, G., Shen, Q., Zhang, C., Ma, J., Mohammed, A., & Zhao, H. (2018). Efficacy and Safety of Gabapentin in the Treatment of Chronic Cough: A Systematic Review. Tuberculosis and respiratory diseases, 81(3), 167–174. https://doi.org/10.4046/trd.2017.0089[↩]
14. Chamberlain, S., Birring, S. S., & Garrod, R. (2014). Nonpharmacological interventions for refractory chronic cough patients: a systematic review. Lung, 192(1), 75–85. https://doi.org/10.1007/s00408-013-9508-y[↩]
15. Connery, A., & Mutvalli, E. (2010). Cough-induced abdominal intercostal hernia. JRSM short reports, 1(3), 23. https://doi.org/10.1258/shorts.2010.010029[↩]
16. Hanak, V., Hartman, T. E., & Ryu, J. H. (2005). Cough-induced rib fractures. Mayo Clinic Proceedings, 80(7), 879–882. https://doi.org/10.4065/80.7.879[↩]
17. Tomar, M., Sharma, G., & Sood, T. Bilateral Subconjunctival Hemorrhage and Periorbital Petechiae due to Chronic Cough in a Child. http://dx.doi.org/10.7869/djo.252[↩]
18. Jo, E. J., & Song, W. J. (2019). Environmental triggers for chronic cough. Asia Pacific allergy, 9(2), e16. https://doi.org/10.5415/apallergy.2019.9.e16[↩]
19. Laniado-Laborín R. (2009). Smoking and chronic obstructive pulmonary disease (COPD). Parallel epidemics of the 21 century. International journal of environmental research and public health, 6(1), 209–224. https://doi.org/10.3390/ijerph6010209[↩]