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; a pharmacologically-effective amount of an antiemetic compound, or a pharmaceutically-acceptable salt thereof; a bioadhesion and/or a mucoadhesion promoting agent; and carrier particles, wherein the active ingredients are presented in particulate form upon the surfaces of the carrier particles, which carrier particles are larger in size than the particles of the active ingredients; and the bioadhesion and/or mucoadhesion promoting agent is, at least in part, presented on the surfaces of the carrier particles.