This invention concerns novel formulations for opioid-based treatments of pain and/or nociception comprising opioid analgesics and 1-(1,2-disubstituted piperidinyl)-4-substituted piperazine derivatives having neurokinin antagonistic activity, in particular NK1 antagonistic activity the use of said formulation for the manufacture of a medicament for the prevention and/or treatment of emesis, pain and/or nociception, in particular in acute and chronic pain treatments, more in particular in inflammatory, post-operative, emergency room (ER), breakthrough, neuropathic and cancer pain treatments and the use of an NK1-receptor antagonist for the manufacture of a medicament for the prevention and/or treatment of respiratory depression and tolerance in opioid-based treatments of pain.The pharmaceutical formulations according to the invention comprise NK1-antagonists according to the general Formula (I) the pharmaceutically acceptable acid or base addition salts thereof, the stereochemically isomeric forms thereof, the N-oxide form thereof and prodrugs thereof, wherein all substituents are defined as in claim 1.The pharmaceutical composition according to the invention reduces to a large extent a number of unwanted side-effects associated with opioid analgesics, in particular respiratory depression and tolerance, thereby increasing the total tolerability of said opioids in pain treatment.