Lingering Cough After a Common Cold: Treatments to Try

Man with a chronic cough.
Man with a chronic cough. Siri Stafford / Getty Images

There are three main types of cough: acute, subacute, and chronic cough. If your cough persists less than 3 weeks, you had an acute cough which resolved. Coughs lasting more than 3 weeks but less than 8 weeks are considered subacute. Post-viral coughs are considered subacute. However, if you have a cough that has lasted more than 8 weeks, your cough will be considered as chronic.

If your cough has persisted more than 21 days after you have had a cold, you likely are now experiencing a post-infectious cough.

While most post-infectious coughs are virus-caused upper respiratory tract infections, they may be from bacterial or fungal infections as well.

Why Am I Coughing?

Coughing is a reflex that can be triggered by both mechanical and chemical receptor stimulation. While commonly attributed to the upper airways, the cough reflex can be triggered in the: upper and lower respiratory tract, pericardium (heart tissue), esophagus, diaphragm and stomach.

Mechanical receptors cause a cough when they are touched or moved. Chemical receptors responds when exposed to: changes in temperature, exposed to acid, or substances similar to capsaicin. Receptors around the larynx, trachea, and bronchi, can be triggered by both mechanical or chemical means. When either mechanical or chemical receptors are activated, you start coughing.

Prevalence of Post-Viral Cough

How likely are you to having a post-viral cough? After experiencing a common viral upper respiratory infection, 11 to 25 out 100 people will have a persistent post-viral cough.

During this time, you will not be contagious, but you will have a nagging cough that may or may not affect your daily activities. If however you acquired a fungal or bacterial upper respiratory infection like Mycoplasma pneumoniae or Bordetella pertussis (bacterial infection), your risk increases to about 25 to 50 percent risk of having a post-infectious cough.

Post-viral coughing tends to also be experienced more frequently in the winter months due to the increase in upper respiratory tract infections. Coughing in general is experience more by school-age children; experiencing approximately 7 to 10 episodes per year. While adults only experience about 2 to 5 episodes per year, the risk is not significantly more for either children nor adults.

Causes of Post-Viral Cough

The reason that you maintain a cough after a upper respiratory tract infection remains unclear. However it is believed that remaining inflammation and compromised upper or lower airway tissue (epithelial) integrity from the cold is responsible. As secretions drain from the upper airways (as with post-nasal drip), the cough reflex can be triggered. Common causes of post-viral cough include:

Do I Need to See a Physician?

In most cases, you will not need to see a doctor for post-viral cough.

However, if your persistent cough worsening or is problematic for you, and has not persisted for longer than 8 weeks, you will want to see a physician for symptomatic relief or further work-up.

Diagnosing Post-Viral Cough

Under normal circumstances you will not need to receive a diagnosis of post-viral cough if you have recently had an upper respiratory tract infection and have had a cough that has not persisted longer than 8 weeks. However if you are having problematic symptoms that are affecting your quality of life, you will want to see a physician. Your doctor will take a thorough history including onset of your cold, as well as characteristics of your current cough. Post-viral cough is diagnosed by excluding other causes (etiologies) of chronic cough. Depending upon your history, your doctor may need to rule out these other causes of chronic cough:

Your doctor will likely not have to test you for each of these other causes. They will determine if any of these should be tested based upon their medical exam and your medical history.

Treating Post-Viral Cough

Without treatment, a post-viral cough will resolve on its own. However if your cough is significantly impacting your quality of life, you may find that the resolution time between 3 and 8 weeks to be too long. If that is the case, you will want to see a physician for symptomatic treatment. There are 2 different main treatment methods that your doctor will evaluate you for to provide the best relief.

In order to properly treat you, your doctor will need to determine whether your post-viral cough is due to post-nasal drip (now referred to as upper airway cough syndrome) or if it is directly related to inflammatory or cough receptor changes from the viral infection.

Cough related to upper airway cough syndrome (UACS) has the same treatment as if you were diagnosed with nonallergenic UACS. As a first line treatment, your doctor will prescribe you a first-generation antihistamine. While this class of medication is more sedating than many newer antihistimines, they are more effective at minimizing your post-viral cough. Antihistamines that may be commonly prescribed includes:

  • brompheniramine
  • chlorpheniramine
  • clemastine

However if you need to work or be more active and the sedating side-effects the antihistamines listed above are undesirable, you can use these secondary generation medications:

Post-viral cough without UACS is directly related to changes in the airway tissue and cough receptors from your viral infection. Treatment for post-viral cough in this case is similar to cough variant asthma. Your doctor in this case may have you take a methacholine or antihistamine challenge test to see if you have bronchial hyperreactivity. Depending on the severity of your symptoms your will be prescribed one or more of the following types of medications:

  • inhaled glucocorticoids
  • inhaled bronchodilators
  • leukotriene receptor antagonists
  • oral prednisone

If your testing does not show bronchial hyperreactivity, it may be useful to trial a course of ipratropium bromide (Atrovent). Atrovent has shown to be successful in post-viral resolution when cough variant asthma is not suspected.

Sources:

Braman, SS. (2006). Postinfectious Cough : ACCP Evidence-Based Clinical Practice Guidelines. Chest. 129(1 Suppl):138S-146S.

Hughes, J & Shield, MD. (2009). Non-specific isolated persistent cough. Paediatrics and Child Health, 19(6):291-293.

Rutter, P. (2013). Respiratory System. Community Pharmacy: Symptoms, Diagnosis and Treatment. Accessed on October 29, 2016 from http://www.clinicalkey.com. (Subscription Required)

Sylvestri, RC & Weinberger, SE. (2014). Evaluation of subacute and chronic cough in adults. Accessed on October 29, 2016 from http://www.uptodate.com. (Subscription Required)

Sylvestri, RC & Weinberger, SE. (2016). Treatment of subacute and chronic cough in adults. Accessed on October 30, 2016 from http://www.uptodate.com. (Subscription Required)

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