Rationale for proposed dosages: Receptor-mediated effects occur at physiological doses (e.g., in children with chronic insomnia effects are achieved at 0.05-0.15mg/kg). However, to achieve non-Melatonin receptor mediated effects (e.g. GABAergic effects, direct free radical scavenging and antioxidant effects) may require supra-physiological doses. 3mg Melatonin is a standard dose used in clinical practice and lower doses do not achieve the same analgesic and anxiolytic effects; however, 3mg may be insufficient to saturate Melatonin receptors and could fall short of the supraphysiological doses we are aiming for to achieve the non-receptor mediated effects. To do this, a higher dose of 10mg will be used which is a logarithmical increase and is still in a clinically acceptable range.