A method for preparing a solid oral dosage form comprising up to about 160 mg of oxycodone or a salt thereof to control pain in substantially all patients is disclosed. The method comprises forming spheroids comprising a spheronising agent and oxycodone or a salt thereof, and coating the spheroids with a controlled-release film coat. Repeated “q12h” (i.e., every 12 hour) administration of the dosage form through steady-state conditions results in a mean maximum plasma concentration of oxycodone up to about 240 ng/ml from a mean of about 2 to about 4.5 hours after administration, and a mean minimum plasma concentration up to about 120 ng/ml from about 10 to about 14 hours after administration.