A Pilot Study Investigating the Efficacy of Minocycline and N-Acetyl Cysteine for Bipolar Depression

The investigators are doing this research study to find out if minocycline alone, N-acetyl cysteine (NAC) alone, or the combination of minocycline and NAC can help people with bipolar depression when added to lithium. The investigators also want to find out if minocycline, NAC, and the combination of minocycline and NAC are safe to take without causing too many side effects. While the U.S. Food and Drug Administration (FDA) has approved minocycline to treat infections and acne and has approved NAC as a mucolytic, the FDA has not approved minocycline, n-acetylcysteine, or the combination of minocycline and n-acetylcysteine to treat bipolar depression. This research study will compare minocycline, n-acetylcysteine, and the combination of n-acetylcysteine and minocycline to placebo. The placebo looks exactly like the other study drugs, but contains neither minocycline nor NAC. During this study participants may get a placebo instead of minocycline, n-acetylcysteine, or the combination of minocycline and n-acetylcysteine. Placebos are used in research studies to see if the results are due to the study drug or due to other reasons.