Inhibitor of analgesic tolerance

摘要

Provided are: an agent for suppressing an undesirable effect of an opioid-type analgesic (opioid), which comprises a compound having adenosine A2A receptor antagonistic activity or a pharmaceutically acceptable salt thereof as an active ingredient; the agent for suppressing an undesirable effect of an opioid-type analgesic (opioid), wherein the undesirable effect of the opioid-type analgesic (opioid) is analgesic tolerance or constipation; the agent for suppressing an undesirable effect of an opioid-type analgesic (opioid), wherein the undesirable effect of the opioid-type analgesic (opioid) is analgesic tolerance; and the like.

主权项

1. A method for suppressing an undesirable effect of an opioid, which comprises administering an effective amount of a compound represented by at least one of formulae (I) to (VIII), or a pharmaceutically acceptable salt thereof: in which R1 represents a hydrogen atom or methyl; R2 and R3 independently represent methyl, ethyl, propyl, butyl or isopropyl; R4, R5 and R6 independently represent a hydrogen atom, methyl, ethyl, methoxy, ethoxy, a fluorine atom, a chlorine atom or a bromine atom; R7 represents methyl, ethyl, propyl, butyl or 3-methylbutyl, each of which is optionally substituted with hydroxy; R8 represents phenyl, pyridyl, pyrimidinyl or 5,6-dihydro-2H-pyridylmethyl, each of which is optionally substituted with 1 to 3 substituents selected from the group consisting of a chlorine atom, methyl, ethyl, methoxy and ethoxy; R9 represents pyridyl or tetrahydropyranyl; R10 and R11 independently represent a hydrogen atom, a fluorine atom or 2-methoxyethoxy; and R12 represents methyl, ethyl, propyl or butyl, wherein said undesirable effect is analgesic tolerance.