Rasagiline, selegiline, isocarboxazid, phenelzine and tranylcypromine are a few examples of monoamine oxidase inhibitors. MAOIs were some of the first antidepressants but have decreased in use due to food and drug interactions, according to MedicineNet.
MAOIs work by inhibiting the monoamine oxidase enzyme from breaking down norepinephrine, serotonin and dopamine, notes MedicineNet. This class of drugs has many side effects, including sudden drops in blood pressure when standing up, dizziness, drowsiness, headache and erectile dysfunction. To avoid dangerous interactions, people on other types of antidepressants should refrain from taking MAOIs . The FDA has not ruled MAOIs as being safe to take by pregnant and nursing mothers, as of 2015.