Melatonin is an endogenous hormone. It is able to promote nighttime sleeping and could induce sleep at daytime in adult and children with the nonpainful diagnostic procedure. However, previous formulation had problems of unstability of product and low oral bioavailability. Melatonin niosomes oral gels are formulated in order to overcome the problem of drug absorption and stability. This study is a randomized, double-blind, three phase crossover design in 15 male volunteers. Melatonin niosomes oral gel will be applied at doses 2.5, 5, and 10 mg with 7 days washout for each period. The pharmacokinetics data, sleep induction effect, and adverse event will be determined.

This study will determine the pharmacokinetics, sleep induction effect, and adverse event after apply melatonin niosomes (MN) oral gel 2.5, 5, and 10 mg per dose in 15 male healthy volunteers. The pharmacokinetic parameters include maximum plasma concentration (Cmax), area under the curve (AUC), time to peak concentration (Tmax), elimination half-life (t1/2). Sleep induction will be determined as sleep onset and duration after use MN oral gels using actigraph and behavior observation. A polysomnography using electrode placement derive from multiple sleep latency test (MSLT) protocol will be used in some subjects. Adverse event will be evaluated by investigator.

Inclusion Criteria:

• male
• age 18-30 years
• body mass index 18.5-25 kg/m2
• general good health and no underlying disease by physical examination and laboratory testing (blood urea nitrogen, creatinine, bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, complete blood count)
• provide signed informed consent for study participation

Exclusion Criteria:

• history of allergies to melatonin products
• use of any drugs, vitamins, or supplements within 30 days before participation
• smoke or alcohol consumption within 1 week before participation
• blood or plasma donation within 30 days before participation