For the last couple of months, I have been using progesterone and estriol creams to treat symptoms of perimenopause. It was difficult enough to deal with the symptoms of PCS without adding perimenopause to the mix. I felt like I was in a perpetual state of PMS. Since starting on the bioidentical hormone, my mood has been brighter, my anxiety and irritability have decreased, I have fewer headaches, my sleep patterns have improved, and I have more energy. Progesterone is known to act as a natural antidepressant. It also has a calming effect. Estrogen alters brain chemistry, and can increase levels of serotonin, dopamine and norepinephrine. Both hormones seem to have a neuroprotective effect. Some interesting studies are being done on the use of progesterone cream to treat TBI. Also, some women with relapsing and remitting MS have reported a remission of their MS symptoms after commencing estriol therapy. For the treatment of PMS, I believe the recommended dosage of progesterone cream is 1/4 tsp, applied to thin areas of the skin, once daily during the last two weeks of a woman's cycle. For the women who decide to try this treatment, it would be interesting to see if there is an improvement in their PCS symptoms as well.