Controlled release hydrocodone formulations

A solid oral controlled-release oral dosage form of hydrocodone is disclosed. The dosage form comprising an analgesically effective amount of hydrocodone or a pharmaceutically acceptable salt thereof, and a sufficient amount of a controlled release material to render the dosage form suitable for twice-a-day administration to a human patient, the dosage form providing a C 12 /C max ratio of 0.55 to 0.85, said dosage form providing a therapeutic effect for at least about 12 hours.