I have two friends who were recently diagnosed with depression. They were both prescribed Prozac by their respective doctors. Both of them are heavy marijuana users and both failed to mention that to their doctors. One has been on Prozac for two months and the other for six weeks. I have noticed that their behavior has become strange: mood swings, paranoia, oversleeping, fatigue. They continue taking their Prozac (20 mg a day) and continue smoking pot. I am afraid that there might be some negative interaction between the substances, one being an antidepressant and the other a depressant. Can you provide some insight?

My friend recently smoked some pot laced with cocaine. First of all, is this possible? Whatever the case may be, he seems to be infatuated with the idea of trying straight coke. I've heard that trying coke for the first time is quite dangerous, true? Also, what are the effects of the high? And how detrimental is coke in general?

I have ADHD and am prescribed 30 mg of Ritalin a day. However I also smoke pot at least once a week. Is it okay to be smoking while on Ritalin?

Many of my friends take Adderall while they drink. What are the possible health risks of doing this? I know Adderall is a stimulant, so can you drink much more alcohol while on it without feeling the effects as much?

Are the health risks of drinking Red Bull and vodka in moderation (two to three) drinks an evening any greater than drinking two or three rum and Cokes, or two or three anything and Mountain Dew?