Codeine-Based Cough Syrup Examples
Codeine phosphate 10 mg per 5 mL combined with guaifenesin 100 mg per 5 mL is a standard FDA-approved formulation available as a prescription cough syrup for adults over 18 years. 1
Important Clinical Context
However, codeine should not be your first-line choice for cough suppression in adults. The American College of Chest Physicians explicitly states that codeine has a greater side effect profile compared to other opioids and is less preferred despite being the most researched drug in this field. 2
Why Codeine Is Not Preferred
Other opioids are superior: When an opioid is indicated for cough, pholcodine, hydrocodone, or dihydrocodeine are preferred over codeine due to better side effect profiles. 2, 3
Non-opioid alternatives are equally effective: Dextromethorphan has no greater efficacy disadvantage compared to codeine but has a much lower adverse side effect profile. 3
Side effect burden: Codeine causes drowsiness, nausea, constipation, and carries risk of physical dependence at effective antitussive doses. 4, 5
Recommended Treatment Algorithm for Adult Cough
Start with non-opioid options first:
First-line: Demulcents such as glycerol-based cough syrups, simple linctus, or butamirate linctus due to low cost and favorable safety profile. 2, 3
Second-line: Dextromethorphan 60 mg (not the subtherapeutic doses in most over-the-counter preparations). 3
Third-line: If opioids become necessary, use pholcodine, hydrocodone, or dihydrocodeine rather than codeine. 2, 3
Codeine dosing if used: 30-60 mg four times daily, though this is not the preferred opioid choice. 3
Common Pitfalls to Avoid
Do not use codeine as first-line therapy: The evidence shows it has significant adverse effects without superior efficacy compared to alternatives. 2, 3
Address underlying causes: Always evaluate for treatable causes of cough (asthma, gastroesophageal reflux, postnasal drip) rather than simply suppressing symptoms. 2, 6
Avoid in productive cough: Codeine is contraindicated when cough serves a physiological clearance function with significant sputum production. 3