Does marijuana produce serotonin?

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.?


How can I overcome my fears?

How do you deal with your fears? I have a fear of other people dying or of myself and others getting a disease. My imagination runs wild with these thoughts, and it's hard to control these worries. I'm always thinking "what if." My friends tell me not to worry unless it actually happens. I know this is true and good advice, but I find it hard to stop worrying. If you could give me some tips on how to control my imagination, it would be much appreciated.