My girlfriend tells me she uses marijuana to calm herself if she is having a stressful day. She has been doing this for many years. She says smoking pot is like self-medicating — it is better than using anti-depressants. She also claims smoking pot helps with depression because of how it helps produce serotonin in the body. What is serotonin and how does it help depression? Does smoking pot really help with managing your anxiety, depression, etc.?

I have a history of "experimentation" (infrequent or occasional use of ecstasy, 'shrooms, and other drugs — mostly prescription pills). I am completely sober now, but am worried about long-term damage to my brain. I used drugs infrequently (no more than three to five times for each substance), but drank regularly. How worried should I be? Is there anything I can do to combat long-term effects?

Recently, I have heard about a new hallucinogen available called salvia dinorium. Some of my friends have tried it and they tell me it is an incredible experience and that when you hallucinate, you have the perception of being brought back in time. Before I even think about trying this, however, I would like to have a more precise idea of what the effects are and what the possible risks of taking salvia are.

I have been reading some studies that state a correlation between the "religious experience" generated by the psilocybin in magic mushrooms and LSD, and an alleviation of body dysmorphic, obsessive compulsive, and other related disorders. I was wondering if this is anything being pursued, whether these effects have been proven, and how long the symptoms are alleviated for if this is the case. Are there any specific conditions that must be met in order to avoid a "bad trip"? I know people experiencing any kind of mood disorder are succeptable as such.