The doctor that prescribed the estrogen patch told me that bipolar women in particular have huge problems with hormonal imbalance and it causes irritability and depression. That's why hormone replacement therapy is so important for bipolar women in particular. Perimenopause, menopause, and post menopause stages tend to wreak unusual havok in bipolar women. HRT is safe and highly effective. If I'd known id feel this good years ago Id have been on it. It has changed my life. I feel so much better.