Melatonin is a naturally produced hormone that we all produce from the B6 in our body which is triggered by darkening light. (which is why we are more sleepy in the winter evenings than the summer ones).
Reseach suggests children with ADHD lack B6 or cannot retain it thus making the production of melatonin harder (or impossible). My DS has been taking a supliment of B6 each day for yonks on this basis.
Melatonin can be bought over the counter in the USA (like we can buy multivits) and is freely available from chemists and supermarkets.
Melatonin can help to promote sleep if you are in a calm and relaxed state and wish to fall asleep, unlike powerful sleeping tablets which are MUCH stronger.
Melatonin can help you drop off but does not necesarily keep you asleep.
A side effect is often the user wakes again after a few hours.
A slow release version is available in the UK called circadin which because it releases slowly it should help keep you asleep and not just get you to sleep.
Circadin is licenced in UK for kids - Melatonin not so (i think) so it is available but much more expensive therefore Doctors prefer Circadin to pure melatonin for this reason (i believe).
Melatonin helps my DS, circadin doesnt (as it didnt help get him to sleep OR keepp him asleep) but that is just my experience.
A relative in the US gives her dogs melatonin when travelling to help them to rest.
I gave my son melatonin before school one day (oops - wrong pill box - we have one for morning and one for evening) and he was absolutely fine and not at all drowsey - proving my point that it is not a "powerful sleeping pill".
But it is yet another reason for the "un-enlightened" to bash us over the head for drugging our un-disciplined brats instead of parenting them properly.
Just my opinion people - you may form your own different opinions and are very free to do so.
PS I would not recomend buying over the internet as you can never be 100% sure on what you are buying but if you ever visit the states and decide to buy some from wall-mart and try them you may form your own opinion based on experience as to how beneficial they may or may not be.
Riven Ritalin should be effective within 30 mins but if the dose is too low you may not notice the effect to any degree until it is increased. Short acting stays in the body for only 3 to 4 hours I believe. Mine started on long acting concerta xl 18mg and for the first time in his life we went to the cinema and he managed to watch the whole film right the way through - It was a "tears welling up moment" for me as I knew then I had made the right decision FOR HIM to agree for him to take this medicine.