Levorphanol

Opioid analgesic drug

Drugbox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 458437606
| IUPAC name = (1R,9R,10R) 17 Methyl 17 azatetracyclo[7.5.3.01,10.02,7]heptadeca 2(7),3,5 trien 4 ol
| image = Levorphanol2DCSD2. svg
| width = 190px
| alt = Structural formula
| image2 = Levorphanol molecule ball. png
| width2 = 200px
| alt2 = Ball and stick model

| pronounce =
| tradename = Levo Dromoran
| Drugs. com =
| MedlinePlus = a682020
| pregnancy US = C
| legal AU = S8
| legal BR = A1
| legal BR comment =
| legal CA = Schedule I
| legal US = Schedule II
| legal UK= Class A
| legal DE = Anlage II
| routes of administration = Oral, intravenous, subcutaneous, intramuscular

| bioavailability = 70% (oral); 100% (IV)
| protein bound = 40%
| metabolism = Hepatic
| elimination half life = 11–16 hours

| IUPHAR ligand = 7595
| CAS number Ref = ? ? | CAS number = 77 07 6
| ATC prefix = None
| ATC suffix =
| ATC supplemental =
| PubChem = 5359272
| DrugBank Ref =
| DrugBank = DB00854
| ChemSpiderID Ref =
| ChemSpiderID = 16736212
| UNII Ref =
| UNII = 27618J1N2X
| KEGG Ref =
| KEGG = D08123
| ChEMBL Ref =
| ChEMBL = 592

| C=17 | H=23 | N=1 | O=1
| smiles = CN1CC[C@]23CCCC[C@H]2[C@H]1Cc4c3cc(O)cc4
| StdInChI Ref =
| StdInChI = 1S/C17H23NO/c1 18 9 8 17 7 3 2 4 14(17)16(18)10 12 5 6 13(19)11 15(12)17/h5 6,11,14,16,19H,2 4,7 10H2,1H3/t14 ,16+,17+/m0/s1
| StdInChIKey Ref =
| StdInChIKey = JAQUASYNZVUNQP USXIJHARSA N
| synonyms = Ro 1 5431 It is the levorotatory enantiomer of the compound racemorphan. Its dextrorotatory counterpart is dextrorphan. It was first described in Germany in 1946. The drug has been in medical use in the United States since 1953.

Levorphanol acts predominantly as an agonist of the μ opioid receptor (MOR), but is also an agonist of the δ opioid receptor (DOR), κ opioid receptor (KOR), and the nociceptin receptor (NOP), as well as an NMDA receptor antagonist and a serotonin norepinephrine reuptake inhibitor (SNRI). As per the World Health Organization, levorphanol is a step 3 opioid and is considered eight times more potent than morphine at the MOR (2 mg levorphanol is equivalent to 15 mg morphine). Relative to morphine, levorphanol lacks complete cross tolerance and possesses greater intrinsic activity at the MOR. Levorphanol's exceptionally high analgesic efficacy in the treatment of neuropathic pain is also conferred by its action on serotonin and norepinephrine transporters, similar to the opioids tramadol and tapentadol, and mutually complements the analgesic effect of its NMDA receptor antagonism. Levorphanol shows a high rate of psychotomimetic side effects such as hallucinations and delirium, which have been attributed to its binding to and activation of the KOR. At the same time however, activation of this receptor as well as of the DOR have been determined to contribute to its analgesic effects. and Virtus Pharmaceuticals in the U. S., and Canada under the brand name Levo Dromoran.