The present invention provides a buprenorphine dimer compound wherein the two buprenorphine portions are linked via an ethylene spacer wherein the spacer is bonded to the two opioid molecules via an ether bond. Pharmaceutical compositions comprising such a buprenorphine dimer drug are also disclosed and the use of such compounds in the treatment of gastrointestinal hyperalgesia generally and in particular diarrhea predominant irritable bowel syndrome.
