There is limited data on the use of minocycline as an adjunctive treatment for psychiatric and neurological conditions in terms of quality and quantity of studies. Studies in psychiatry suggest an overall benefit of minocycline, especially in schizophrenia, where it seems to act through anti-inflammatory and neurotransmitter pathways to exert its effects. In the field of neurology, however, despite some positive effects, larger controlled trials are needed to reach definitive conclusions, including exploring possible mechanisms of action. Overall, minocycline appears safe and tolerable for both neurological and psychiatric conditions. More work is needed to improve evidence for definitive conclusions but minocycline also appears to be a promising candidate for the treatment of psychiatric disorders in particular.