Chemistry:Dextrorphan

From HandWiki
Short description: Psychoactive cough suppressant medication
Dextrorphan
Dextrorphan.svg
Dextrorphane 3d.gif
Clinical data
Other namesDXO, Dextrorphanol
ATC code
  • None
Legal status
Legal status
  • US: Unscheduled[1]
Identifiers
CAS Number
PubChem CID
ChemSpider
UNII
ChEMBL
Chemical and physical data
FormulaC17H23NO
Molar mass257.377 g·mol−1
3D model (JSmol)
 ☒N☑Y (what is this?)  (verify)

Dextrorphan (DXO) is a psychoactive drug of the morphinan class which acts as an antitussive or cough suppressant and dissociative hallucinogen. It is the dextrorotatory enantiomer of racemorphan; the levorotatory enantiomer is levorphanol. Dextrorphan is produced by O-demethylation of dextromethorphan by CYP2D6. Dextrorphan is an NMDA antagonist and contributes to the psychoactive effects of dextromethorphan.[2]

Pharmacology

Pharmacodynamics

Site Ki (nM) Species Ref
NMDAR
(MK-801)
486–906 Rat [3]
σ1 118–481 Rat [3]
σ2 11,325–15,582 Rat [3]
DOR 34,700 Rat [3]
KOR 5,950 Rat [3]
SERT 401–484 Rat [3]
NET ≥340 Rat [3]
DAT >1,000 Rat [3]
5-HT1A >1,000 Rat [3]
5-HT1B/1D 54% at 1 μM Rat [3]
5-HT2A >1,000 Rat [3]
α1 >1,000 Rat [3]
α2 >1,000 Rat [3]
β 35% at 1 μM Rat [3]
D2 >1,000 Rat [3]
H1 95% at 1 μM Rat [3]
mAChRs 100% at 1 μM Rat [3]
nAChRs 1,300–29,600
(IC50)
Rat [3]
VDSCs ND ND ND
Values are Ki (nM), unless otherwise noted. The smaller the value, the more strongly the drug binds to the site.

The pharmacology of dextrorphan is similar to that of dextromethorphan (DXM). However, dextrorphan is much more potent as an NMDA receptor antagonist as well much less active as a serotonin reuptake inhibitor, but retains DXM's activity as a norepinephrine reuptake inhibitor.[4] It also has more affinity for the opioid receptors than dextromethorphan, significantly so at high doses.

Pharmacokinetics

Dextrorphan has a notably longer elimination half-life than its parent compound, and therefore has a tendency to accumulate in the blood after repeated administration of normally dosed dextromethorphan formulations.[citation needed] It is further converted to 3-HM by CYP3A4 or glucuronidated.[5]

Society and culture

Legal status

Dextrorphan was formerly a Schedule I controlled substance in the United States , but was unscheduled on October 1, 1976.[6]

Research

Dextrorphan was under development for the treatment of stroke, and reached phase II clinical trials for this indication, but development was discontinued.[7]

Environmental presence

In 2021, dextrorphan was identified in >75% of sludge samples taken from 12 wastewater treatment plants in California . The same study associated dextrorphan with estrogenic activity by using predictive modelling, before observing it in in vitro. [8]

See also

References

  1. Bensinger, Peter (October 1, 1976). "Dextrophan and Nalbuphine; Removal from Schedules". https://www.govinfo.gov/content/pkg/FR-1976-10-01/pdf/FR-1976-10-01.pdf. 
  2. "Psychotropic effects of dextromethorphan are altered by the CYP2D6 polymorphism: a pilot study". Journal of Clinical Psychopharmacology 18 (4): 332–337. August 1998. doi:10.1097/00004714-199808000-00014. PMID 9690700. 
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 3.14 3.15 3.16 3.17 Cite error: Invalid <ref> tag; no text was provided for refs named pmid26826604
  4. "Comparison of the effects of dextromethorphan, dextrorphan, and levorphanol on the hypothalamo-pituitary-adrenal axis". The Journal of Pharmacology and Experimental Therapeutics 309 (2): 515–522. May 2004. doi:10.1124/jpet.103.060038. PMID 14742749. 
  5. "Comparative contribution to dextromethorphan metabolism by cytochrome P450 isoforms in vitro: can dextromethorphan be used as a dual probe for both CTP2D6 and CYP3A activities?". Drug Metabolism and Disposition 29 (11): 1514–20. November 2001. PMID 11602530. http://dmd.aspetjournals.org/cgi/pmidlookup?view=long&pmid=11602530. 
  6. DEA. "Lists of: Scheduling Actions Controlled Substances Regulated Chemicals". http://www.deadiversion.usdoj.gov/schedules/orangebook/orangebook.pdf. 
  7. "Dextrorphan - AdisInsight". http://adisinsight.springer.com/drugs/800009336. 
  8. "Using Estrogenic Activity and Nontargeted Chemical Analysis to Identify Contaminants in Sewage Sludge". Environmental Science & Technology 55 (10): 6729–6739. May 2021. doi:10.1021/acs.est.0c07846. PMID 33909413. Bibcode2021EnST...55.6729B.