Monoamine oxidase inhibitors (MAOIs) are a class of antidepressants that work by inhibiting the enzyme monoamine oxidase in the brain. Monoamine oxidase is responsible for breaking down neurotransmitters such as serotonin. Increased amounts of these neurotransmitters help to stabilize mood and reduce anxiety.
Given that MAOIs have a large number of food and drug interactions, some of which are potentially fatal, these medications are usually only prescribed if selective serotonin reuptake inhibitors (SSRIs) are not helpful.

