wow! INH is both a antidepressant and a antibiotic. please read article
In 1951, two physicians from Sea View Hospital on Staten Island, Irving Selikoff and Edward Robitzek, began clinical trials on two new anti-tuberculosis agents from Hoffman-LaRoche, isoniazid and iproniazid. Only patients with a poor prognosis were initially treated; nevertheless, their condition improved dramatically. Selikoff and Robitzek noted "a subtle general stimulation . . . the patients exhibited renewed vigor and indeed this occasionally served to introduce disciplinary problems." The promise of a cure for tuberculosis in the Sea View Hospital trials was excitedly discussed in the mainstream press. In 1952, learning of the stimulating side effects of isoniazid, the Cincinnati psychiatrist Max Lurie tried it on his patients. In the following year, he and Harry Salzer reported that isoniazid improved depression in two thirds of their patients and coined the term antidepressant to describe its action. A similar incident took place in Paris, where Jean Delay, head of psychiatry at Sainte-Anne Hospital, found out from his pulmonology colleagues at Cochin Hospital about the side effects of isoniazid. In 1952, before Lurie and Salzer, Delay, with the resident Jean-Francois Buisson, reported the positive effect of isoniazid on depressed patients. For reasons unrelated to its efficacy, isoniazid as an antidepressant was soon overshadowed by the more toxic iproniazid, although it remains a mainstay of tuberculosis treatment. The mode of antidepressant action of isoniazid is still unclear. It is speculated that its effect is due to the inhibition of diamine oxidase, coupled with a weak inhibition of monoamine oxidase A.