The present invention provides a dosage form comprising at least one form oftapentadol, with or without a secondanalgesic, and at least one opioid antagonist, wherein tapentadol is presentin an optimal or suboptimal amount and the said antagonistis present in an amount effective to improve the efficacy and or reduce theside effects of tapentadol. The present inventionfurther provides a method of treating pain and pain related conditions byadministering to a patient in need thereof, a dosage formcomprising at least one form of tapentadol, with or without a secondanalgesic, and at least one opioid antagonist, wherein tapentadolis present in an optimal or suboptimal amount and the said antagonist ispresent in an amount effective to improve the efficacyand or reduce the side effects of tapentadol.
