MAOI

Monoamine oxidase inhibitors (MAOIs) are chemicals that inhibit the activity of the monoamine oxidase enzyme family. They have a long history of use as medications prescribed for the treatment of depression. They are particularly effective in treating atypical depression. They are also used in the treatment of Parkinson's disease and several other disorders.

Because of potentially lethal dietary and drug interactions, monoamine oxidase inhibitors have historically been reserved as a last line of treatment, used only when other classes of antidepressant drugs (for example selective serotonin reuptake inhibitors and tricyclic antidepressants) have failed. New research into MAOIs indicates that much of the concern over their dangerous dietary side effects stems from misconceptions and misinformation, and that despite the proven effectiveness of this class of drugs, it is underutilized and misunderstood in the medical profession. New research also questions the validity of the perceived severity of dietary reactions, which has historically been based on outdated research. However, this research also notes that many practitioners have a poor understanding of drug interactions, and 'drug interactions can be serious, and concomitant medication use must be stringently overseen' as they 'can cause a dangerous or fatal serotonin syndrome/ toxicity'.

Newer MAOIs such as selegiline (typically used in the treatment of Parkinson's disease) and the reversible MAOI moclobemide provide a safer alternative and are now sometimes used as first-line therapy.

MAOIs have been found to be effective in the treatment of panic disorder with agoraphobia,social phobia, atypical depression or mixed anxiety disorder and depression, bulimia, and post-traumatic stress disorder, as well as borderline personality disorder. MAOIs appear to be particularly effective in the management of bipolar depression according to a recent retrospective-analysis. There are reports of MAOI efficacy in obsessive-compulsive disorder (OCD), trichotillomania, dysmorphophobia, and avoidant personality disorder, but these reports are from uncontrolled case reports.

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