Definition - What does Letrozole mean?
Letrozole is an oral medication that inhibits the enzyme aromatase which is responsible for the conversion of androgens (hormone precursors) to estrogens. Letrozole is indicated for use in breast cancer. It reduces the growth of cancerous tissues estrogen is responsible for signaling.
Letrozole is often used as adjunct therapy in anovulatory infertility (inability to release an egg). Letrozole is also used to treat fertility in polycystic ovarian syndrome (PCOS) and endometriosis.
Letrozole is also known as the brand name Femara.
FertilitySmarts explains Letrozole
Letrozole suppresses estrogen creation which then, in turn, increases natural gonadotropin release. Gonadotropins create a signal for egg release or ovulation. Often letrozole is combined with gonadotropins in order to reduce the amount required. When used for ovulation induction, letrozole is taken daily for five days starting on day three of menses followed by intrauterine insemination.
In women with PCOS, letrozole for ovulation induction has higher birth rates compared to clomiphene citrate.
Women with endometriosis suffer from painful uterine tissue found outside the uterine wall. Letrozole reduces estrogen which is responsible for this tissue growth. Letrozole used in combination with other therapies has been shown to reduce pelvic pain and has illustrated safety up to six months of use.
Letrozole has special protective handling instructions to keep the tablet intact (avoid crushing or splitting). It is advised to use gloves when touching the drug. Common side effects include edema (fluid build up), hot sweats, gastrointestinal upset, muscle pain or arthritis, dizziness, and headache. Long term effects include bone loss. Patients with liver impairment should be warned of potential increased risk of side effects and may require a dose adjustment. Patients should be warned to use caution when driving or operating machinery due to potential dizziness and fatigue until they know how the medication will affect them.