The short answer is yes. As usual, there are a few caveats to be considered. While cannabis is very well tolerated by the human body and no long term toxicity has been observed, the body does accommodate to the regular ingestion of anything. This means that the amount required to produce the same effect may increase a bit over time. With cannabis, this process seems to stop rather quickly so people never acquire the kind of great tolerances seen with other medications. With use limited to before sleep I would expect minimal issues if the cannabis were discontinued. When patients become used to taking cannabis throughout the day there is some "withdrawal" noted on stopping completely, but for most people this is a barely noticeable phenomenon and resolves quickly with no treatment of any kind. I would be happier if a patient of mine took daily cannabis for sleep than if they used most OTC or prescription sleep aids on a daily basis.
drelkind