Monoamine oxidase inhibitors (MAOIs) are a class of medications used primarily to treat depression. They work by blocking the action of the enzyme monoamine oxidase, which breaks down neurotransmitters like serotonin, norepinephrine, and dopamine in the brain. By inhibiting this enzyme, MAOIs increase the levels of these neurotransmitters, helping to improve mood and alleviate depressive symptoms. MAOIs are typically prescribed when other antidepressants, such as selective serotonin reuptake inhibitors (SSRIs), are ineffective. However, they require dietary restrictions to avoid serious interactions with certain foods containing tyramine, which can lead to dangerous increases in blood pressure.