GnRH agonist
Pronunciation: gee-en-ar-aitch AG-oh-nist
Also written as: GnRH — Gonadotropin-Releasing Hormone Agonist
Medication that suppresses ovarian hormone production by initially stimulating then suppressing the hypothalamic-pituitary-gonadal axis.
Full Definition
Gonadotropin-releasing hormone (GnRH) agonists are synthetic hormones that initially stimulate the release of FSH and LH, but with continuous administration lead to downregulation of GnRH receptors and subsequent suppression of ovarian function. This creates a reversible medical menopause state. In gynecology, they are commonly used to treat conditions like endometriosis, uterine fibroids, and in assisted reproductive technology protocols. Common examples include leuprolide (Lupron) and goserelin (Zoladex). Side effects often mirror those of menopause, including hot flashes and bone density concerns with long-term use.
Usage
Usage note: Distinguish from GnRH antagonists, which provide immediate suppression without initial stimulation.
In Context
- "The patient was started on a GnRH agonist to shrink her fibroids preoperatively." — treatment plan
- "Monthly GnRH agonist injections successfully controlled her endometriosis symptoms." — follow-up notes