Used historically as an antidepressant, this compound was one of the first monoamine oxidase inhibitors (MAOIs) developed for the treatment of depression. It works by increasing levels of neurotransmitters such as serotonin, dopamine, and norepinephrine in the brain, which helps improve mood and emotional well-being. It was also investigated for use in treating tuberculosis due to its structural relation to isoniazid, though its primary medical application became psychiatric. Due to safety concerns, including hepatotoxicity and dietary interactions leading to hypertensive crises, it has been largely discontinued and replaced by safer antidepressants. Today, it is mainly of historical and research interest in the development of psychopharmacology.