Codeine is effective as an antitussive at what dose?

Codeine is effective as an antitussive at what dose?

• A. 5 mg
• B. 30 mg
• C. 60 mg
• D. 15 mg

Answer: (D)

Codeine works as an antitussive by acting centrally on the medullary cough center through mu-opioid receptors. The cough-suppressing effect occurs at lower doses than those needed for analgesia, so a small dose can reliably reduce cough. About 15 mg per dose is in the range that provides effective cough suppression in most adults, whereas 5 mg is often too low to be consistently effective. Larger doses, such as 30 or 60 mg, produce analgesia and raise the risk of adverse effects like sedation, constipation, nausea, and even respiratory depression. Individual response also varies with CYP2D6 metabolism, so some people may experience stronger effects (ultra-rapid metabolizers) or diminished cough suppression (poor metabolizers).

Codeine works as an antitussive by acting centrally on the medullary cough center through mu-opioid receptors. The cough-suppressing effect occurs at lower doses than those needed for analgesia, so a small dose can reliably reduce cough. About 15 mg per dose is in the range that provides effective cough suppression in most adults, whereas 5 mg is often too low to be consistently effective. Larger doses, such as 30 or 60 mg, produce analgesia and raise the risk of adverse effects like sedation, constipation, nausea, and even respiratory depression. Individual response also varies with CYP2D6 metabolism, so some people may experience stronger effects (ultra-rapid metabolizers) or diminished cough suppression (poor metabolizers).