**Important note on melatonin in Australia:** You asked about melatonin, which is a Schedule 4 medication in Australia and requires a prescription from your GP. While melatonin has strong evidence for sleep support (especially for jet lag and shift work), magnesium and glycine are excellent non-prescription alternatives with good evidence. If you'd like to explore melatonin, ask your doctor — they can prescribe it if appropriate for your situation. Also, if your sleep issues persist beyond 4–6 weeks of supplementation, consider a blood test to check for deficiencies in iron, B12, or vitamin D, which commonly affect sleep quality in Australia.