Aim: Intranasal melatonin encapsulated in nanosized niosomes was preclinically evaluated.
Methodology: A formula of melatonin niosomes (MN) was selected through physicochemical and cytotoxic data for pharmacokinetic, pharmacodynamics and toxicity studies in male Wistar rats.
Results: Intranasal MN was bioequivalent to intravenous injection of melatonin, providing therapeutic level doses. Acute and subchronic toxicity screening showed no abnormal signs, symptoms or hematological effects in any animals. Transient nasal irritations with no inflammation were observed with intranasal MN, leading it to be categorized as relatively harmless.
Conclusion: The intranasal MN could deliver melatonin to the brain to induce sleep and provide delayed systemic circulation, relative to intravenous injection and also distribute to peripheral tissue.
Keywords: in vitro cytotoxicity; nanosized melatonin niosomes; pharmacodynamic; pharmacokinetic; toxicity.