For me, Melatonin (just 300mcg, a very small dose) and cutting out caffeine and chocolate are sometimes required. Two less obvious things that work for me: -

For me, Melatonin (just 300mcg, a very small dose) and cutting out caffeine and chocolate are sometimes required. Two less obvious things that work for me: - Massage the back of my neck rigorously before sleep. Probably this improves blood flow to the brain. - Unlock the window handle slightly, to get a constant flow of air towards the head. Probably I need more oxygen (or lower CO2) than usual because this doesn’t work for my wife.