Betamethadol

{{Short description|Synthetic opioid analgesic drug}}

{{technical|date=September 2017}}

{{Drugbox

| IUPAC_name = (3S,6R)-6-(dimethylamino)-4,4-diphenyl-3-heptanol

| image = Betamethadol.svg

| image_class = skin-invert-image

| alt = Skeletal formula

| width = 190

| image2 = Betamethadol molecule ball.png

| alt2 = Ball-and-stick model of betamethadol

| CAS_number = 17199-55-2

| CAS_supplemental =

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 57ANR1Z628

| ATC_prefix = None

| ATC_suffix =

| PubChem = 10064061

| KEGG = D12675

| ChEMBL = 162243

| ChemSpiderID = 8239601

| C=21 | H=29 | N=1 | O=1

| smiles = O[C@H](C(c1ccccc1)(c2ccccc2)C[C@H](N(C)C)C)CC

| StdInChI = 1S/C21H29NO/c1-5-20(23)21(16-17(2)22(3)4,18-12-8-6-9-13-18)19-14-10-7-11-15-19/h6-15,17,20,23H,5,16H2,1-4H3/t17-,20+/m1/s1

| StdInChIKey = QIRAYNIFEOXSPW-XLIONFOSSA-N

| bioavailability =

| protein_bound =

| metabolism =

| elimination_half-life =

| excretion =

| pregnancy_category =

| legal_AU = S9

| legal_BR = A1

| legal_BR_comment = {{Cite web |author=Anvisa |author-link=Brazilian Health Regulatory Agency |date=2023-03-31 |title=RDC Nº 784 - Listas de Substâncias Entorpecentes, Psicotrópicas, Precursoras e Outras sob Controle Especial |trans-title=Collegiate Board Resolution No. 784 - Lists of Narcotic, Psychotropic, Precursor, and Other Substances under Special Control|url=https://www.in.gov.br/en/web/dou/-/resolucao-rdc-n-784-de-31-de-marco-de-2023-474904992 |url-status=live |archive-url=https://web.archive.org/web/20230803143925/https://www.in.gov.br/en/web/dou/-/resolucao-rdc-n-784-de-31-de-marco-de-2023-474904992 |archive-date=2023-08-03 |access-date=2023-08-16 |publisher=Diário Oficial da União |language=pt-BR |publication-date=2023-04-04}}

| legal_CA = Schedule I

| legal_US = Schedule I

| legal_DE = Anlage I

| routes_of_administration =

}}

Betamethadol (INN), or β-methadol, also known as betametadol, is a synthetic opioid analgesic.{{cite book | author = F.. Macdonald | title = Dictionary of Pharmacological Agents | url = https://books.google.com/books?id=A0THacd46ZsC&pg=PA1294 | accessdate = 15 May 2012 | year = 1997 | publisher = CRC Press | isbn = 978-0-412-46630-4 | page = 1294}} It is an isomer of dimepheptanol (methadol), the other being alphamethadol (α-methadol).{{cite book | author = United Nations Office on Drugs and Crime | title = Dictionnaire Multilingue Des Stupéfiants Et Des Substances Psychotropes Placés Sous Contrôle International | url = https://books.google.com/books?id=RPAphv7h4-IC&pg=PA103 | accessdate = 15 May 2012 | year = 2006 | publisher = United Nations Publications | isbn = 978-92-1-048117-5 | page = 103}} Betamethadol is composed of two isomers itself, L-β-methadol, and D-β-methadol. Based on structure-activity relationships it can be inferred that both isomers are likely to be active as opioid analgesics, similarly to those of betacetylmethadol (β-acetylmethadol).{{cite journal | vauthors = Newman JL, Vann RE, May EL, Beardsley PM | title = Heroin discriminative stimulus effects of methadone, LAAM and other isomers of acetylmethadol in rats | journal = Psychopharmacology | volume = 164 | issue = 1 | pages = 108–14 |date=October 2002 | pmid = 12373424 | doi = 10.1007/s00213-002-1198-8 | s2cid = 19815273 }}