Help me with my brother....?

ok well my mom called him a few days ago at night to see where he was cuz it was late and he needed to get home and he said he was at meijer with his friend and then later he called to see if he could follow his friend home becuase my brother said his friends car was actin up but i think his friend was drunk and i am afraid that my brother has been hanging out with this guy too much and i think maybe he is taking drugs becuase he hasnt been acting and nice and stuff... he just hasnt been hisself. so do you think he is gettin drunk and tain drugs and stuff? if u have anyquestions just ask me and put this question on your watch list and i will check this question alot and post your question and my answer if you really care about my brother who i am very scared about