ISSN 2286-6493
Journal of Asian Association of Schools of Pharmacy

An intravenous injection of melatonin: formulation, stability, pharmacokinetics and pharmacodynamics  Research Paper 

Jeffrey Roy Johns1*, Chatchawan Chenboonthai1, Nutjaree Prateepavanich Johns1, Aucharaporn Saengkrasat1, Ratiya Kuketpitakwong1, Supatra Porasupatana1
Faculty of Pharmaceutical Science, Khon Kaen University, Khon Kaen, Thailand.


    Two different intravenous (IV) formulations for melatonin at strength of 5 mg/mL; one using 2- hydroxypropyl-B-cyclodextrin and propylene glycol to increase solubility and stability, and a second having additional antioxidant and chelating agent to reduce oxidation and hydrolysis were investigated. Both formulations were tested for clarity, pH stability, sterility, endotoxins, particulate matter according to US Pharmacopoeia Revision 31 (USP31), and photostability according to ICH guideline (ICH (Q1B), Option2), accelerated stability at 25oC/75% RH for 6 months, and real time stability for one year at 30oC/75%RH, according to IHC guidelines. The pharmacokinetics of the IV dose were investigated in Wistar rats, and the antioxidant effect determined ORAC analysis of rat plasma. Both formulations passed USP tests for purity and stability, although the formulation without antioxidant exhibited more color and pH change over the testing period. Formulation 2 showed expected pharmacodynamics on injection in rat (20 μg/200 μL/rat), and plasma showed a significant increase (p<0.05) of ORAC antioxidant capacity from 10 min after injection. This study provides evidence of suitable intravenous formulations of melatonin for bioavailability or studies.  


1 melatonin
2 intravenous injection
3 formulation
4 stability
5 pharmacokinetics

Published in

JAASP Volume 1 No. 1
January - March, 2012

Page: 25-37

View and Download

Click here to download fullpaper (Size: 200.67 KB.)


Journal of Asean Association of Schools of Pharmacy
Copyright © 2018