Subacute Post-Viral Cough Management

Clinical Presentation and Diagnosis

The American College of Chest Physicians recommends that a subacute post-viral cough (10 days duration) with upper airway cough syndrome (UACS) be treated with a first-generation antihistamine/decongestant combination, as most post-infectious coughs resolve within 3-8 weeks 1
A post-infectious etiology is suggested by initial viral prodrome, including watery nasal discharge, mild fever, and dry cough with sensation of phlegm, which are classic for viral upper respiratory infection 2, 3
The timing of the cough, with a 10-day duration, places it in the subacute category (3-8 weeks), where post-infectious cough is the leading diagnosis 1
Symptom evolution, including progressive improvement with residual night throat itchiness and cough attacks strongest at night, is characteristic of post-viral airway inflammation and UACS 4

The American College of Chest Physicians recommends starting a first-generation antihistamine/decongestant combination, such as diphenhydramine 25-50mg + pseudoephedrine 60mg, three to four times daily, to address the post-nasal drip component causing throat irritation and nocturnal cough 1, 5
Dextromethorphan-containing cough suppressants are more effective than other cough suppressants, such as Strepsils (amyloglucosidase), for symptomatic relief 2, 3
Honey and lemon or menthol lozenges can be used for throat irritation, and paracetamol can be used for any residual discomfort 2, 3

Red flags, including hemoptysis, progressive dyspnea or breathlessness, persistent or recurrent fever, constitutional symptoms, and cough persisting beyond 3 weeks total duration, require immediate action, including obtaining a chest X-ray 2, 3, 6, 7
If symptoms persist beyond 3 weeks total, a chest X-ray should be obtained, and specialist referral should be considered to evaluate for UACS, asthma/cough-variant asthma, gastroesophageal reflux disease (GERD), and non-asthmatic eosinophilic bronchitis 2, 3, 4, 7

Most post-infectious coughs resolve within 3-8 weeks without specific intervention, and with appropriate UACS treatment, improvement should be seen within 1-2 weeks 1, 4
Follow-up should be scheduled in 2 weeks to assess treatment response, and if no improvement, a chest X-ray should be obtained, and sequential trials for asthma and GERD should be considered 1, 8