What is "monoamine oxidase inhibitor"

n. any of a group of antidepressant drugs that inhibit the action of monoamine oxidase in the brain and so allow monoamines to accumulate [syn: 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 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also questions the validity of the perceived severity of dietary reactions, which has historically been based on outdated research.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'.