The drug scene at AUP is kept on the down-low and isn't really a big deal. The most prevalent drug is pot, and alcohol is widely consumed since France has a lower drinking age than the United States. There isn't any pressure to participate when it comes to this, but if you want something, then you'll know how to find it. Drinking is a huge part of the social scene, and it's ten times more likely that a lot of booze will be downed than drugs. This is because the students have access to the most popular bars, clubs, and parties in Paris, and pretty much everyone knows someone who can get a group of people in somewhere selective.
When it comes to drugs, the students are very respectful when it comes to someone's personal choices. There's not a lot of peer pressure to give into, so the only person anyone has to be honest with is himself. A great time can still be had hanging around your friends who drink, even if you don't; just don't lecture them. There is almost always a mutual acceptance of choices when it comes down to it. Besides, when among people who know how to have a great time, things like this are hardly an important issue.