What is the best way to reverse side effects of natural progesterone cream?

Stop using it.: Stop using it. Most 'natural Progesterone creams' do not contain any Progesterone at all, and often contain plant extracts that are estrogenic in effect. In my clinical view there is no good use for these creams. Talk with your doctor about alternatives to accomplish what you need.

Lower the dose: During the normal menstrual cycle, Progesterone levels vary greatly. Thus, for many women who use Progesterone the dose has to vary depending on estrogen levels and other factors. For adjustments, cream rather than capsules allow for better regulation of dose. Generally start with a low dose such as 1/8 teaspoon of Progesterone cream. And work up slowly.