Esmirtazapine 2D structure.svg
Clinical data
Routes of
ATC code
  • none
Legal status
Legal status
  • In general: uncontrolled
Pharmacokinetic data
MetabolismLiver (CYP2D6)[1]
  • (S)-1,2,3,4,10,14b-hexahydro-2-methylpyrazino(2,1-a)pyrido(2,3-c)(2)benzazepine
CAS Number
PubChem CID
ECHA InfoCard100.056.994 Edit this at Wikidata
Chemical and physical data
Molar mass265.360 g·mol−1
3D model (JSmol)
Melting point114 to 116 °C (237 to 241 °F)
Solubility in waterSoluble in methanol and chloroform mg/mL (20 °C)
  • CN1CCN2c3c(cccn3)Cc4ccccc4[C@H]2C1
  • InChI=1S/C17H19N3/c1-19-9-10-20-16(12-19)15-7-3-2-5-13(15)11-14-6-4-8-18-17(14)20/h2-8,16H,9-12H2,1H3/t16-/m1/s1 checkY
 ☒NcheckY (what is this?)  (verify)

Esmirtazapine (ORG-50,081) is a drug which was under development by Organon for the treatment of insomnia and vasomotor symptoms (e.g., hot flashes) associated with menopause.[2][3][4][5] Esmirtazapine is the (S)-(+)-enantiomer of mirtazapine and possesses similar overall pharmacology, including inverse agonist actions at H1 and 5-HT2 receptors and antagonist actions at α2-adrenergic receptors.[2][6] As of March 2010, Merck terminated internal clinical development program for esmirtazapine, for hot flashes and insomnia, for strategic reasons.[7]

See also


  1. ^ "A population analysis on the effects of the CYP2D6 deficiency on pharmacokinetics and exposure of esmirtazapine in healthy volunteers" (PDF).
  2. ^ a b "Future Treatments for Depression, Anxiety, Sleep Disorders, Psychosis, and ADHD --".
  3. ^ "A Long-Term Safety Study of Org 50081 in Elderly Outpatients With Chronic Primary Insomnia (176005)(P05697) - Full Text View -". 7 January 2021. ((cite journal)): Cite journal requires |journal= (help)
  4. ^ Teegarden BR, Al Shamma H, Xiong Y (2008). "5-HT(2A) inverse-agonists for the treatment of insomnia". Current Topics in Medicinal Chemistry. 8 (11): 969–76. doi:10.2174/156802608784936700. PMID 18673166.
  5. ^ Lewis V (November 2009). "Undertreatment of menopausal symptoms and novel options for comprehensive management". Current Medical Research and Opinion. 25 (11): 2689–98. doi:10.1185/03007990903240519. PMID 19775194. S2CID 206964530.
  6. ^ Depression and bipolar disorder: Stahl's essential psychopharmacology. Cambridge, UK: Cambridge University Press. 2008. ISBN 978-0-521-88663-5.
  7. ^ "Archived copy" (PDF). Archived from the original (PDF) on 2011-08-05. Retrieved 2011-05-03.((cite web)): CS1 maint: archived copy as title (link)