Azelastine

Azelastine
Clinical data
Trade namesAstelin, others
AHFS/Drugs.comMonograph
MedlinePlusa603009
License data
Pregnancy
category
  • AU: B3
Routes of
administration		Eye drops, nasal spray, by mouth
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability40% (intranasal) [4]
Metabolitesdesmethylazelastine (active) [4]
Onset of actionWithin 1 hour [4]
Elimination half-life22 hours [4]
Duration of action12 hours [4]
Identifiers
  • (RS)-4-[(4-Chlorophenyl)methyl]-2-(1-methylazepan-4-yl)-phthalazin-1-one
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
CompTox Dashboard (EPA)
ECHA InfoCard100.133.278 Edit this at Wikidata
Chemical and physical data
FormulaC22H24ClN3O
Molar mass381.90 g·mol−1
3D model (JSmol)
  • Clc1ccc(cc1)CC\3=N\N(C(=O)c2ccccc2/3)C4CCCN(C)CC4
  • InChI=1S/C22H24ClN3O/c1-25-13-4-5-18(12-14-25)26-22(27)20-7-3-2-6-19(20)21(24-26)15-16-8-10-17(23)11-9-16/h2-3,6-11,18H,4-5,12-15H2,1H3 checkY
  • Key:MBUVEWMHONZEQD-UHFFFAOYSA-N checkY
  (verify)

Azelastine, sold under the brand name Astelin among others, is a H1 receptor-blocking medication primarily used as a nasal spray to treat allergic rhinitis (hay fever) and as eye drops for allergic conjunctivitis.[5][6] Other uses may include asthma and skin rashes for which it is taken by mouth.[7] Onset of effects is within minutes when used in the eyes and within an hour when used in the nose.[8] Effects last for up to 12 hours.[8]

Common side effects include headache, sleepiness, change in taste, and sore throat.[8] It is unclear if use is safe during pregnancy or breastfeeding.[9] It is a second-generation antihistamine and works by blocking the release of a number of inflammatory mediators including histamine.[7][8]

Azelastine was patented in 1971 and came into medical use in 1986.[10] It is available as a generic medication.[3][11] In 2022, it was the 124th most commonly prescribed medication in the United States, with more than 5 million prescriptions.[12][13]

  1. ^ Cite error: The named reference Astelin FDA label was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Optivar FDA label was invoked but never defined (see the help page).
  3. ^ a b "FDA Approves a Nasal Antihistamine for Nonprescription Use". U.S. Food and Drug Administration (FDA) (Press release). 17 June 2021. Retrieved 21 June 2021.
  4. ^ a b c d e Lieberman P, Hernandez-Trujillo V, Lieberman J, Frew AJ (2008). "Antihistamines". Clinical Immunology. Elsevier. pp. 1317–1329. doi:10.1016/b978-0-323-04404-2.10089-2. ISBN 9780323044042. After intranasal administration, its systemic bioavailability is approximately 40%. Azelastine has an onset of action within the first hour of administration and reaches peak activity at 1–3 hours after administration. Duration of activity is about 12 hours. Intranasal administration results in maximal plasma concentrations in 2–3 hours. ... The half-life of the parent compound is 22 hours ...
  5. ^ British national formulary : BNF 76 (76 ed.). Pharmaceutical Press. 2018. p. 1169. ISBN 9780857113382.
  6. ^ Al-Ahmad M, Hassab M, Al Ansari A (21 December 2020). "Allergic and Non-allergic Rhinitis". Textbook of Clinical Otolaryngology. Cham: Springer International Publishing. pp. 241–252. doi:10.1007/978-3-030-54088-3_22. ISBN 978-3-030-54087-6. S2CID 234142758.
  7. ^ a b Aronson JK (2015). Meyler's Side Effects of Drugs: The International Encyclopedia of Adverse Drug Reactions and Interactions. Elsevier. p. 782. ISBN 9780444537164.
  8. ^ a b c d "Azelastine Hydrochloride Monograph for Professionals". Drugs.com. American Society of Health-System Pharmacists.
  9. ^ "Azelastine ophthalmic (Optivar) Use During Pregnancy". Drugs.com. Retrieved 26 March 2019.
  10. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 548. ISBN 9783527607495.
  11. ^ "First Generic Drug Approvals". U.S. Food and Drug Administration (FDA). 8 July 2024. Retrieved 9 July 2024.
  12. ^ "The Top 300 of 2022". ClinCalc. Archived from the original on 30 August 2024. Retrieved 30 August 2024.
  13. ^ "Azelastine Drug Usage Statistics, United States, 2013 - 2022". ClinCalc. Retrieved 30 August 2024.