Nonproductive Cough Management

Introduction to Nonproductive Cough Treatment

The American College of Chest Physicians recommends that patients with nonproductive cough should first try honey and lemon mixture as a simple, inexpensive, and often effective first-line treatment, with evidence of patient-reported benefit 1
Voluntary cough suppression through central modulation of the cough reflex may be sufficient to reduce cough frequency in some patients 1

Dextromethorphan is the recommended antitussive because it has equivalent efficacy to codeine but with significantly fewer adverse effects, including no drowsiness, nausea, constipation, or physical dependence 1
Standard over-the-counter doses of dextromethorphan are often subtherapeutic, and maximum cough suppression occurs at 60 mg, with a dose-response relationship demonstrated 1, 2
Typical dosing of dextromethorphan is 10-15 mg three to four times daily, with a maximum daily dose of 120 mg 2
For severe cough requiring maximum suppression, a single 60 mg dose of dextromethorphan can be used 2
First-generation sedating antihistamines, such as diphenhydramine, can suppress cough and are particularly useful when cough disrupts sleep due to their sedative properties 1
Menthol by inhalation suppresses the cough reflex when inhaled, providing acute but short-lived relief 1, 2

In patients with chronic obstructive pulmonary disease (COPD) or asthma, treat the underlying disease first rather than suppressing cough, and cough suppression should be avoided if cough serves a protective clearance function 1
In patients with impaired renal function, no dose adjustment of dextromethorphan is required, as it is primarily metabolized hepatically by CYP2D6, not renally excreted 2
In patients with impaired hepatic function, use caution with dextromethorphan, and consider lower doses or increased dosing intervals in severe hepatic impairment 1, 2

Start with non-pharmacological approaches, such as honey and lemon mixture, and voluntary cough suppression 1
If additional relief is needed, use dextromethorphan 30-60 mg, but not subtherapeutic doses 1, 2
For nocturnal cough disrupting sleep, use first-generation antihistamines with sedative properties 1
For quick but temporary relief, use menthol inhalation 1, 2
For postinfectious cough, first try inhaled ipratropium, then consider inhaled corticosteroids if quality of life is affected, and short-course prednisone for severe paroxysms 1, 2, 3

Dextromethorphan should be used for short-term symptomatic relief only 2
If cough persists beyond 3 weeks, discontinue antitussive therapy and perform a full diagnostic workup to evaluate for alternative diagnoses 2
If postinfectious cough persists beyond 8 weeks, consider diagnoses other than postinfectious cough 1