Sis I knew alotttaaa people who were on drugs and still are..many quit and some are still on it...well if you are a respected person to the person then i think you should talk to him and bring the facts on the table..tell him tht he's way smarter then a person using drugs and that what's the point of it?? why is he using and selling it?? Recommend him to go to a masjid and tell him that drugs are all worthless used for temporary pleasure or happiness..once addicted to weed it's really hard to get off and only a person's self-determination will drag them away from it and the fact that it's hard to buy it..

Tell him stories of deaths that have happened because of these drugs and it is basically suicide in other words because it's slowly killing you inside..and suicide is haraam so he shouldn't be doing it...Why waste his time doing something like this when he could use his time doing something beneficial..if you can even recommend him to this forum..manyy broz and sisters here can help him..K inshallah i hpe i helped..Salamualikum