How Long Should a Cough Last?

An acute (sudden) cough illness (ACI) is one of the main reasons people seek outpatient medical care from a family physician or pediatrician. Many of these cases are caused by acute bronchitis or bronchiolitis. Bronchitis is inflammation of the bronchial tubes, which are airways that connect that windpipe to the lungs.

Bronchiolitis is inflammation of the bronchioles, which are small airways that branch off the other small airways connected to the lungs.

The cause of ACI is usually a virus but patients often seek antibiotic treatment for it. The problem, though, is that while antibiotics are good at treating bacterial infections, they do not work at treating viruses. When antibiotics are prescribed for viral illnesses, it is referred to as antibiotic overuse. Overuse of antibiotics increases the risk that antibiotic-resistant bacteria will develop.

Many doctors are prone to prescribing medications in response to patient pressure (or pressure from the family). These pressures result from patient expectations on how long an acute cough should last without treatment.

In the most recent issue of the Annals of Family Medicine, researchers examined how closely patient expectations of acute cough duration matched reality. After a comprehensive literature search, the researchers found 19 studies across the world that helped them determine the average length of an untreated acute cough in otherwise healthy adults. They found that the average length of any cough was about 18 days. The average length of a cough that produced something to spit out (i.e., productive cough) was 13.9 days. 

The researchers then surveyed 493 adults in Georgia to determine their expectation on the average duration of an acute-onset cough. Depending on the specific scenario, patients expected an average cough duration of about 7 to 9 days. As the researchers explained, if the expectation of acute cough duration is wrong, it can lead to false conclusions by the patient in terms of the effectiveness of the antibiotic. For example, if a patient with an acute viral cough expects that it should only last for 7 days, seeks antibiotic treatment, and receives it, the patient will likely falsely conclude that the antibiotic cured the cough when it would have resolved anyway in 18 days. The researchers provided evidence supporting that such beliefs exist.

The researchers concluded that a better understanding of the typical duration of acute cough could reduce patient demands for antibiotics. They suggested that doctors help educate their patients about the normal length of acute cough and that they should only seek care if the cough worsens or if other alarming signs and symptoms develop such as fever, shortness of breath, or coughing up blood.

Suggested reading: Breaking the Antibiotic Habit: A Parent's Guide to Coughs, Colds, Ear Infections, and Sore Throats

Reference: Ebell, M., Lundgren, J., Youngpairoj, S. (2013). How Long Does a Cough Last? Comparing Patient’s Expectations with Data from a Systematic Review of the Literature. Annals of Family Medicine, 11, 1, 5-13.