adult humans. nac has been hypothesized to exert beneficial effects through its modulation of glutamate and dopamine neurotransmission as well as its antioxidant properties. bipolar disorder in bipolar disorder, n-acetylcysteine has been repurposed as an augmentation strategy for depressive episodes in light of the possible role of inflammation in the pathogenesis of mood disorders. nonetheless, meta-analytic evidence shows that add-on n-acetylcysteine was more effective than placebo only in reducing depression scales scores (low quality evidence), without positive effects on response and remission outcomes, limiting its possible role in clinical practice to date. covid-19 acetylcysteine is being considered as a possible treatment for covid-19.