Letrozole is a Selective nonsteroidal inhibitor of the aromatase enzyme system; it inhibits the conversion of androgens to estrogen.In adult nontumor- and tumor-bearing female animals, letrozole is as effective as ovariectomy in reducing uterine weight, elevating blood serum luteinizing hormone, and inflicting the regression of estrogen-dependent tumors. In distinction to ovariectomy, treatment with letrozole doesn’t cause a rise in serum follicle-stimulating hormone. Letrozole selectively inhibits gonadal steroidogenesis, however, has no important effect on adrenal mineralocorticoid or glucocorticoid synthesis.Letrozole inhibits the aromatase enzyme by competitively binding to the heme of the cytochrome P450 subunit of the enzyme, leading to a reduction of estrogen synthesis in all tissues. Treatment of women with letrozole significantly lowers blood serum estrone, estradiol and estrone sulfate and has not been shown to significantly have an effect on adrenal corticosteroid synthesis, aldosterone synthesis, or synthesis of thyroid hormones. Learn More About Femara here
