Although generally considered benign and chronic, endometriosis (the presence of endometrial tissues and stroma beyond the uterus), can cause pain and infertility. Clinicians generally have 2 options for women who develop endometriosis: surgery or medical therapies. Surgery can alleviate many of the signs and symptoms of endometriosis, but is not always successful. Medical therapies include a number of different hormonal approaches.
The journal Drugs has published a review of current and emerging treatments for endometriosis. Consensus among experts is that endometriosis can only be treated by removing the unwanted tissue or reducing estrogen exposure, so that it will shrink. The goal is to address active symptoms, prevent recurrence, and control pain.
First-line therapies for endometriosis include the nonsteroidal anti-inflammatory drugs (NSAIDs), combined oral contraceptives, and other estroprogestins, and progestins.
Clinicians often employ NSAIDs to treat endometriosis, capitalizing on their analgesic and anti-inflammatory properties. Although a Cochrane review recently indicated there is insufficient high-quality evidence to support the use of NSAIDS for endometriosis-related pain, women report that NSAIDs relieve their pain effectively. No one NSAID seems to be more effective than any other.
Clinicians often prescribe estroprogestins including the oral, vaginal, or transdermal patch formulations in sequence or continuously for endometriosis. Good evidence supports their uses, and this inexpensive intervention rarely causes adverse effects.
Progestins are also considered first-line therapy, and additionally offer the advantage of low-cost. These, too, have low rates of adverse effect, and are available in a number of different administration routes.
Women who failed to respond to estroprogestins or progestins often need to step up to gonadotropin-releasing hormone agonists. These second line therapies are often administered using injectable depot formulations. They suppress ovarian production of estrogen and cause amenorrhea. Lowered estrogen levels eventually cause endometriosis tissues outside of the uterus to regress. Amenorrhea prevents new peritoneal seedlings. Unfortunately, GNRH agonists are associated with several adverse events, including lipid profile changes, depression, hot flashes, urogenital atrophy, and bone mineral density loss. Often, clinicians must treat intolerable adverse effects with additional treatment including low-dose oral contraceptives.
Traditionally, clinicians have used danazol to treat endometriosis. This drug is also expensive, and available as a generic. However, its propensity to cause androgenic adverse effects has decreased his popularity in recent years.
Experimentally, researchers are looking at aromatase inhibitors. They tend to be more expensive than other medications, and also have significant adverse effect profiles. Additionally, researchers are looking at GnRH antagonists. Little information is available about these drugs at this point.
Ferrero S, Barra F, Leone Roberti Maggiore U. Current and emerging therapeutics for the management of endometriosis. Drugs. 2018;78(10):995-1012.