Bipolar I Disorder is a serious mental illness that causes extreme mood swings. This study looks at Endoxifen, a drug related to Tamoxifen, to see if it helps people with Bipolar I Disorder. In this study, some participants will get Endoxifen, and others will get a placebo (a pill with no medicine) to compare results. Protein Kinase C (PKC) is a protein in the brain that affects mood, and too much PKC activity can cause bipolar symptoms. Endoxifen might help by reducing PKC activity. The goal is to see if Endoxifen is safe and works well for treating bipolar symptoms.
- The study requires a 21-day stay in a hospital.
- Participants must be between 18 and 65 years old.
- Participants will not receive Endoxifen if they have other serious health issues.