[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"notifications-list":3,"$f2t3fh8v8ca7qe":5},{"data":4},[],{"data":6,"error":11},{"id":7,"documentId":8,"slug":9,"name":10,"medical_code":11,"short_description":12,"alternate_name":11,"disambiguating_description":11,"citations":13,"drugs":36,"specialties":47,"cover":11},880,"thf1gfygrqti1fe4bsg1w32g","competitive-opioid-antagonists","Competitive Opioid Antagonists",null,"Opioid receptors are G protein-coupled receptors for the endogenous opioid peptides; the mu receptor is the main physiological target of most clinically important opioid analgesics, and mu-mediated inhibition of voltage-gated calcium channels on central presynaptic terminals of primary afferent nociceptors is thought to be a primary mechanism of analgesia at the spinal level. This class narrows opioid antagonism by naming how the block is exerted: competitive binding is the interaction of two or more ligands with the same binding site, one displacing the other, so a competitive antagonist occupies the agonist's own site. As MED-RT populates the class it holds alvimopan, described in the NCI Thesaurus as a selective and competitive antagonist at mu-opioid receptors in the gut, and nalbuphine, whose FDA-approved label records it as an agonist at kappa opioid receptors and an antagonist at mu opioid receptors.",[14,20,24,28,32],{"claims":15,"source":16,"licence":17,"source_url":18,"retrieved_at":19},"Mu-type opioid receptor as a GPCR for endogenous opioids; 'OPRM1 is the main physiological target for most clinically important opioid analgesics' and OPRM1-mediated inhibition of voltage-gated calcium channels on central presynaptic terminals of primary afferent nociceptors as a primary mechanism of spinal analgesia.","UniProtKB P35372","not stated on source page","https:\u002F\u002Frest.uniprot.org\u002Funiprotkb\u002FP35372.json","2026-09-19",{"claims":21,"source":22,"licence":17,"source_url":23,"retrieved_at":19},"'The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.'","MeSH descriptor D001667, 'Binding, Competitive' (concept M0002504 scope note)","https:\u002F\u002Fid.nlm.nih.gov\u002Fmesh\u002FM0002504.json",{"claims":25,"source":26,"licence":17,"source_url":27,"retrieved_at":19},"'Alvimopan is a selective and competitive antagonist at mu-opioid receptors, found in myenteric and submucosal neurons and the immune cells of the lamina propria in the human gut.'","NCI Thesaurus concept C49096, Alvimopan","https:\u002F\u002Fapi-evsrest.nci.nih.gov\u002Fapi\u002Fv1\u002Fconcept\u002Fncit\u002FC49096?include=full",{"claims":29,"source":30,"licence":17,"source_url":31,"retrieved_at":19},"'Nalbuphine is an agonist at kappa opioid receptors and an antagonist at mu opioid receptors.'","DailyMed SPL - Nalbuphine hydrochloride injection, Hospira","https:\u002F\u002Fdailymed.nlm.nih.gov\u002Fdailymed\u002Fservices\u002Fv2\u002Fspls\u002Fa99fe500-f52b-483c-807c-178f1a78a02b.xml",{"claims":33,"source":34,"licence":17,"source_url":35,"retrieved_at":19},"Class membership: alvimopan and nalbuphine only - the receipt that butorphanol and pentazocine are not in this class.","RxNav RxClass class members (MED-RT), classId N0000175686","https:\u002F\u002Frxnav.nlm.nih.gov\u002FREST\u002Frxclass\u002FclassMembers.json?classId=N0000175686&relaSource=MEDRT&rela=has_MoA",[37,41],{"id":38,"documentId":39,"slug":40,"name":40,"active_ingredient":11,"dosage_form":11,"administration_route":11},1763,"ggaow9cocj3o7j8i8b0hzd9r","pentazocine",{"id":42,"documentId":43,"slug":44,"name":45,"active_ingredient":46,"dosage_form":11,"administration_route":11},1599,"thxhnapb1uy8c1bfk5hziy4a","butorphanol","Butorphanol","Butorphanol tartrate",[]]