I've never heard of that but I do use low doses of melatonin to help my son sleep. Bash me if you must, but I don't consider it "drugging" him when he comes to me at midnight crying b/c he is physically incapable of slowing his brain down enough for him to sleep. AND YES...we have tried tiring him out running around, lavender baths, chamomile teas, white noise, bedtime stories, etc ... it's either this or he doesn't sleep.
I never did either, my mil and also my best friend who was an r n of courses suggested about my teething baby to put whiskey on his gums to help him sleep and stop aching - no way. I let them use soft radios as white noise to help all of my kids sleep.