Randomized, double-blind, placebo-controlled study of the efficacy and safety of biphasic immediate-release/extended-release hydrocodone bitartrate/acetaminophen tablets for acute postoperative pain.

Randomized, double-blind, placebo-controlled study of the efficacy and safety of biphasic immediate-release/extended-release hydrocodone bitartrate/acetaminophen tablets for acute postoperative pain.