N-acetylcysteine in bipolar disorder
N-acetylcysteine, a precursor of glutathione, is an important antioxidant in the brain and reduces oxidative stress. Increased oxidative stress and altered glutathione metabolism have been reported in bipolar and major depressive disorder.153 A randomized controlled trial in bipolar patients on mood stabilizers found that those who were given adjunctive N-acetylcysteine 2 g/day showed a significant improvement in depression, mania, quality of life, and social and occupational functioning compared with placebo.154 Dean et al reviewed the literature on the therapeutic effect of N-acetylcysteine in psychiatric disorders, including bipolar disorder, and found it to be beneficial in patients with bipolar depression.155 It is well tolerated by patients with bipolar disorder, although it needs to be taken for 8 weeks (2 g/day) to achieve a positive response.