Minocycline as Adjunctive Treatment in Depression
Dysregulation of the immune system is implicated as an etiological factor in the pathogenesis of depression. Evidence suggests that individuals that develop depression in the context of inflammation may constitute a distinct subtype. 
The role of the immune system may also explain the association between stress, depression and heart disease.
Therefore, drugs that modulate the immune system have gained attention in the treatment of depression. Recently published meta-analyses have shown there is support for the use of compounds such as infliximab (monoclonal antibody used in autoimmune diseases), celecoxib (NSAID used in rheumatoid arthritis), aspirin (common pain relief with potential immunotherapy properties), and N-acetylcysteine (a modified amino acid that is purported to have antioxidant properties). , 
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