Originally Posted by
EnnuiStasis 
Mental Health & Brain: The most fascinating and widely recognized health benefit of smoking is its ability to seemingly alleviate symptoms of mental illnesses, including anxiety and schizophrenia. According to an article published in 1995 in Neuroscience & Biobehavioral Reviews, schizophrenics have much higher smoking rates than people with other mental illnesses, and appear to use it as a method of self-medicating. The article postulates that nicotine found in cigarettes reduces psychiatric, cognitive, sensory, and physical effects of schizophrenia, and also provides relief of common side effects from antipsychotic drugs.
Yeah, smoking cigarettes is well known for its properties to enhance stimulation and relaxation experiences. Certainly I found smoking to ring both those bells for myself.
Still though, nicotine is poisonous, and causes cancer, so it will not likely itself be used medicinally in its pure form just yet, if ever. As for how it effects the brain chemistry, this too is problematic because nicotine is very powerful and can easily cause desensitisation which then leads to tolerence, which makes its use therafter unpredictable and risk-filled as to which proper dosages would be effective and healthy.
Interesting for sure.
Me, I'm glad I quit nonethless, because the known possible health benefits are not worth the known fatal risks which accompanies smoking.