Persistent Cough After Cold Medicine: When Duration, Not Dose, Matters

Many patients report that their cough remains unchanged after taking cold medicine. While a stronger cough suppressant is often added, a substantial portion of non‑resolving coughs are due to a shift in the underlying disease process, not a lack of medication. This piece discusses that distinction and limits its scope to over‑the‑counter (OTC) products. Peripheral antitussives such as levodropropizine and teobromine, as well as codeine‑type agents, are classified as prescription medicines in Korea and are therefore excluded. The first step in counseling is to consider the duration of the cough rather than the drug itself. A literature review of the natural course of acute cough reported an average duration of 17.8 days. In a survey of 493 adults, patients’ expected cough duration differed from the observed average (the source text is truncated, so further details are unavailable).