Pharmacologic management of endometriosis

The incidence, pathogenesis, staging, and treatment of endometriosis are reviewed, with an emphasis on pharmacologic management of this condition. Endometriosis--the presence of ectopic endometrial tissue--can be found in 15-25% of infertile women and may be found in 1-5% of all women between menarche and menopause. Although the pathogenesis of endometriosis is uncertain, the most tenable etiologic theory is a combination of celomic metaplasia and retrograde menstruation. Staging is based on the American Fertility Society classification scheme, with stage I being the mildest and stage IV the most severe form of the disease. The management of endometriosis depends on the extent of the disease, the severity of the symptoms, the age of the patient, and the patient's desire for future fertility. Treatment modalities include expectant management, surgery, induction of a pseudopregnancy state with hormonal therapy (e.g., oral contraceptives), or induction of a pseudomenopausal state. The induction of a pseudomenopausal state with the use of oral danazol gained widespread favor in the 1970s as the treatment of choice in patients with endometriosis, but therapy is often associated with unpleasant adverse effects. Gonadotropin-releasing hormone (GnRH) agonists may provide a safe and clinically effective alternative to danazol therapy in patients with endometriosis. Results of a multicenter study comparing nafarelin with danazol for treatment of endometriosis indicated no significant differences between treatment groups with respect to improvements in disease state and symptomatology. The most common adverse effect associated with nafarelin therapy is hot flashes. The GnRH agonist nafarelin is as effective as danazol or oral contraceptives for the treatment of endometriosis and causes fewer adverse reactions. GnRH agonists may replace danazol as the treatment of choice in patients with endometriosis.