Postinfectious cough is defined as a subacute cough, with symptoms lasting between 3 and 8 weeks. The preceding infection triggers an inflammatory cascade , increasing bronchial sensitivity and mucus production, while reducing its elimination. Postinfectious cough affects 11% to 25% of adults after a respiratory infection. |
The diagnosis is by exclusion.
This clinical diagnosis requires a previous respiratory infection, absence of worrisome findings on physical examination, and exclusion of other symptoms of subacute cough (e.g., asthma, chronic obstructive pulmonary disease [COPD], gastroesophageal reflux disease, or use of inhibitors). angiotensin-converting enzyme).
Pertussis should be considered in patients with paroxysmal cough, posttussive vomiting, and inspiratory stridor.
Warning signs and prolonged duration of cough should prompt further study
The presence of hemoptysis, systemic symptoms, dysphagia, excessive dyspnea, or hoarseness warrants investigations such as a chest x-ray. Other red flags include a history of recurrent pneumonia or a long history of smoking. A cough that lasts more than 8 weeks is considered chronic and requires additional evaluation, such as a lung function test to rule out asthma or COPD.
There is no evidence to support drug treatment that is associated with harm
Systematic reviews of randomized controlled trials evaluating inhaled corticosteroids, bronchodilators, and oral agents for postinfectious cough concluded that there is no evidence of benefit. Most trials found that cough symptoms improve without medication, highlighting the self-limiting nature of post-infectious cough. Furthermore, due to adverse effects and drug costs, pressurized metered-dose inhalers emit powerful greenhouse gases. Unauthorized use of inhalers can also tax the medical supply chain.
Patient peace of mind and education are essential
Reassuring patients that postinfectious cough is time-limited and resolves on its own can reduce unnecessary prescriptions, including antibiotics. Doctors should advise patients to schedule a follow-up appointment for further testing if the cough has not resolved within 8 weeks or if new symptoms appear.
