Melatonin is for falling asleep. It’s not like taking Benadryl or ambien or Nyquil, it won’t keep you asleep.
Parents give it to the kids with ASD and ADHD who have naturally lower levels of melatonin and they can’t seem to turn off their brains at bedtime. So for people with ADHD and/or Aspergers could benefit greatly.
Pregnant women with preeclampsia are now being treated with melatonin. Melatonin is a massive free radical scavenger above 20 mg. Oncology studies add it to the daily plan of cancer patients. But not everyone can handle that level. It causes nightmares for some.