The invention is directed in part to oral dosage forms comprising a
combination of an orally analgesically effective amount of an opioid
agonist and an orally active opioid antagonist, the opioid antagonist
being included in a ratio to the opioid agonist to provide a combination
product which is analgesically effective when the combination is
administered orally, but which is aversive in a physically dependent
subject. Preferably, the amount of opioid antagonist included in the
combination product provides at least a mildly negative, "aversive"
experience in physically dependent addicts (e.g., precipitated abstinence
syndrome).