How do immediate-release and extended-release opioid formulations differ in clinical use?

• A. Immediate-release provides rapid, short-duration analgesia ideal for breakthrough pain or titration; extended-release provides steadier, longer-lasting analgesia for chronic, persistent pain and reduces dosing frequency.
• B. The two have identical pharmacokinetics; selection is random.
• C. Immediate-release is used for cancer pain only; extended-release for non-cancer.
• D. Extended-release provides short bursts of pain relief.

Answer: (A)