Bioavailability of a New Oral Spray Melatonin Emulsion Compared with a Standard Oral Formulation in Healthy Volunteers
- *Corresponding Author:
- Antonella Bartoli
Clinical Pharmacokinetics in Transplantations and
Autoimmune Diseases, Foundation IRCCS Policlinico San Matteo
Piazzale Golgi n.2, 27100 Pavia, Pavia Italy
E-mail: [email protected]
Received Date: August 23, 2012; Accepted Date: September 20, 2012; Published Date: September 25, 2012
Citation: Bartoli AN, De Gregori S, Molinaro M, Broglia M, Tinelli C, et al. (2012) Bioavailability of a New Oral Spray Melatonin Emulsion Compared with a Standard Oral Formulation in Healthy Volunteers. J Bioequiv Availab 4: 096-099. doi: 10.4172/jbb.1000120
Copyright: © 2012 Bartoli AN, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Background and Objective: Melatonin, a pineal gland hormone secreted at night, is involved in the sleep-wake
cycle and has been extensively used in the treatment of primary sleeping disorders. Up to 90% of blood melatonin is
cleared by the liver in a single passage, thus its half-life is very short (30-60 minutes). To avoid the first pass effect
responsible for up to 90% loss of the melatonin oral dosage and to ensure rapid onset of activity, a new food grade
liquid emulsion has been formulated in a spray form, which assures an additional increase of the contact surface and
the possibility of efficient mucosal absorption.
The purpose of the present study was to investigate the bioavailability profile of this new food grade liquid
emulsion compared with a standard melatonin formulation in commercially available oral tablets.
Methods: In a single-dose, open-label, crossover study, eight subjects were randomly assigned to receive 5
mg of oral spray or oral melatonin (tablet). After a washout of one week, plasma was collected at six hours post
dosing and assayed by a validated liquid chromatography tandem mass spectrometry method to determine the main
Results and Discussion: The student t Test for paired data highlighted a significant difference between Cmax
values (p=0.021) and the AUC (p=0.045). The absorption rate (Tmax) of the two melatonin formulations did not show
statistically significant differences (Friedman test). The amount of melatonin reaching the systemic circulation after
oral spray administration was significantly higher than after oral tablet administration.