What Are the Medications for Endometriosis?
To halt or slow the progression of endometriosis, the doctor will start by prescribing medication. Surgery is recommended only if medications fail, unless there is severe or advanced disease or a suspicion of cancer.
- The primary therapy initially recommended for the pain of endometriosis is a nonsteroidal antiinflammatory drug (NSAID) such as ibuprofen (Motrin or Advil) or naproxen sodium (Aleve).
- If NSAIDs are not sufficient for pain control, her doctor may prescribe stronger medications, even including opioid (narcotic) drugs. Care should be taken when using these drugs due to the possibility for abuse and addiction.
Depending on the severity of the disease, the next step in the treatment of endometriosis is to slow or halt the proliferation of the endometrial tissue outside of the uterus. Different treatment strategies may be employed to change the hormone levels that promote endometriosis.
Gonadotropin-releasing hormone analogs (GnRH analogs)
Gonadotropin-releasing hormone analogs (GnRH analogs) may be prescribed to relieve pain and reduce the size of endometriosis implants. GnRH analogs are administered by nasal spray or by intramuscular injections at one to three month intervals. These drugs suppress estrogen production by the ovaries, resulting in a cessation of menstrual periods, and symptoms mimicking those of the menopausal transition includinghot flashes, vaginal dryness, irregular vaginal bleeding, mood changes, fatigue, and loss of bone density (osteoporosis). Fortunately, many of the annoying side effects due to estrogen deficiency can be avoided by administering estrogen in pill form (called "add back" therapy).
Oral contraceptive pills
Oral contraceptive pills (OCPs, estrogen and progesterone in combination, birth control pills) are also occasionally used to treat endometriosis in women who also desire contraception. Weight gain, breast tenderness, nausea, and irregular bleeding may be mild side effects.
Progestins [for example, medroxyprogesterone acetate (Provera), norethindrone acetate (Aygestin, Camila, Errin, Jolivette, Nor-QD, Nora-Be, Ortho Micronor), norgestrel acetate (Ovrette)] are sometimes used in women who do not obtain pain relief from OCPs. Side effects include breast tenderness, bloating, weight gain, irregular uterine bleeding, and depression.
Danazol (Danocrine) is a synthetic drug that stimulates high levels of androgens (male type hormones) and low estrogen levels by interfering with ovulation and ovarian production of estrogen. This drug is effective for pain relief and shrinkage of endometriosis implants, but has a high incidence of side effects including:
- weight gain,
- decreased breast size,
- oily skin,
- hirsutism (male pattern hair growth),
- deepening of the voice,
- hot flashes,
- changes in libido, and
- mood changes.
All of these changes except for voice changes are reversible, but the return to normal may take many months. Danazol should not be taken by women with certain types of liver, kidney, and heart conditions.
Another strategy is the administration of drugs known as aromatase inhibitors [anastrozole (Arimidex) and letrozole (Femara) are examples]. These drugs disrupt estrogen formation within the endometriosis implants themselves. They also inhibit estrogen production in other areas of the body. Aromatase inhibitors cause significant bone loss with prolonged use. A further drawback is that these drugs stimulate development of multiple follicles at ovulation, so they must be used with caution in premenopausal women and may be combined with another medication such as a GnRH agonist or oral contraceptive pill to suppress the development of follicles.