There is provided pharmaceutical compositions for the treatment of pain comprising a pharmacologically-effective amount of an opioid analgesic, or a pharmaceutically-acceptable salt thereof, presented in particulate form upon the surfaces of carrier particles comprising a pharmacologically-effective amount of an opioid antagonist, or a pharmaceutically-acceptable salt thereof, which carrier particles are larger in size than the particles of the opioid analgesic. The compositions are also useful in prevention of opioid abuse by addicts.