I see myself scaling WAY back after I graduate, if not sooner. The unfortunate fact of being a drug user is that it does bias good people against you. It can alienate you from someone who would end up being a best friend, a wife or husband, an employer, etc. Drugs are fun, and can definately be used responsibly by alot of alot of people, but as long as they are stigmatized to the extent they are in our culture, drug user is definately a "master status" and will affect your social/work life unless you are completely secretive (which, in my opinion, defeats the entire purpose of getting high). So, I'll have my fun while I can, but when I entire the real world after I get my degree(s) any substance other than alcohol will be very rarely, if ever, consumed by me. At some point it's not worth fighting the stigma and it's time to throw in the towel and give in to what society thinks.
Not to mention that I want to be able to enjoy life WITHOUT substances, as I feel a certain guilt whenever I get to the point that I need [insert drug here] to get through the day, or to have a good time with friends. It's also pretty undeniable that all drugs are bad for your mental and physical health on some level or another... with very few (if any?) exceptions.