My brother smokes weed every day of his life and so do all my friends well most of them any way in my opinion they are still the same people they were b4 it, weed isn't harmful really yes there are sum short term memory loss but in the end it doesn't do any real damage, but in the end it is illegal and thats what counts, but also look at from his point of view meds are horrible and mayb for him weed is a much better drug than the presricption ones cause they are more dangerous than most illegal ones, drugs are bad all round there is no denying it, but weed is one of the least harmful there is in fact you even get madical weed which is given to cancer patients to ease the pain, but that is no means for your son to be smoking it, it just means that you should just try and understand WHY he is smoking it in the first place b4 you even try to send him to rehab or whatever.