Medical Treatments for Endometriosis

Similar to the lining of the uterus, endometriosis usually responds to estrogen and progesterone, the hormones that control your menstrual cycle. The natural fluctuations (or rise and fall of the amounts) of these hormones can increase the activity of endometriosis and aggravate symptoms, whereas steady medical doses of estrogens, progestins, and other medications that decrease natural hormone production can lessen endometriosis “flare ups.”

As a general rule, women are less likely to have problems with endometriosis before their first menstrual period or after menopause. On the other hand, women with endometriosis tend to experience more symptoms around their period. It is also believed that endometriosis may form when menstrual tissue flows backwards through the fallopian tubes and implants in the abdominal cavity and pelvis. Thus, suppressing (stopping) your period with the following hormonal medications can help relieve endometriosis-related pain and prevent endometriosis from developing or becoming worse over time.

Continuous Estrogen/Progestin Hormonal Therapy

Medications containing a combination of an estrogen and a progestin can be used to control your periods and suppress the activity of endometriosis. The most common combination of estrogen and progesterone is in the form of the birth control pill, but hormones can also be delivered by a vaginal contraceptive ring (Nuvaring®) that lasts 3-4 weeks or a patch (Ortho Evra®) that you wear on your skin and change weekly. All hormonal medications appear to be most effective against endometriosis when used in a continuous fashion. This means that you use an active pill, ring, or patch daily, and skip the hormone-free week when you would normally have your period.

Instructions on How to take Continuous Combined Hormonal Therapy

  • Birth Control Pills - Take one active pill every day at the same time
  • Vaginal Ring - Insert a new vaginal ring every 3-4 weeks
  • Patch - Change your patch weekly

Continuous use is as easy as skipping the inactive pills in your pill pack or replacing your ring/patch as soon as it would normally be time to remove the old one. In doing so, you will decrease the number of bleeding days that you have and prevent pain associated with your period.

Continuous combined estrogen and progestin therapy is safe and well-tolerated by most women. The estrogen/progestin therapies also provide reliable contraception but do not protect from sexually transmitted diseases (STDs). The most frequently encountered problem is unscheduled “breakthrough” bleeding or spotting, which usually becomes less frequent the longer you are on the hormone treatment. Taking the pill at the same time every day and avoiding missed pills helps to prevent break-through bleeding. Some women who are at higher risk for blood clots or stroke should not take hormonal therapies with estrogen. Talk to your gynecologist to see whether or not continuous combined estrogen/progestin treatment is right for you.

Continuous Progestin Hormonal Therapy

Progestins, or “progesterone-like” hormones, are one of the components found in combined estrogen/progestin treatments, like the birth control pill (see medical treatments: continuous estrogen/progestin). Progestins alone are also effective in treating endometriosis. When taken in a long-term continuous fashion, progestins tend to thin the lining of the uterus which stops regular periods and lessens the chance for break-through bleeding or spotting and has similar activity against endometriosis lesions themselves.

There are various forms of synthetic progesterone called, “progestins” that are used to treat endometriosis. When treating young women, we prefer to start with a daily pill, such as a progesterone “birth control pill” sometimes referred to as a “mini-pill” or norethindrone acetate (Aygestin®). These medications should be taken at the same time every day to lessen the chance of unscheduled “breakthrough” bleeding (spotting) and pain. Setting the alarm on your cell phone can be a good reminder to take your medication at the same time each day.

The “mini-pill” is considered a slightly less effective contraceptive and Aygestin is not considered a contraceptive and may not protect against pregnancy. There are at least two long-acting progestin-only contraceptive methods, which may be useful in treating endometriosis: (1) injectable medroxyprogesterone (Depo-Provera®) and (2) the levonorgestrel intrauterine device (Mirena® IUD).

Progestin-only treatments

Method: Pills
Examples: Norethindrone acetate (Aygestin®), Progestin only birth control pills (Camila, Nor-QD), Medroxyprogesterone acetate (Provera®)
How Medication is Taken: Daily Pills Method: Injections Examples: Medroxyprogesterone (Depo-Provera®) How Medication is Taken: One shot every 3 months

Method: Intrauterine Device (IUD)
Examples: Levonorgestrel-releasing IUD (Mirena®)
How Medication is Taken: Small “t-shaped” device inserted into the uterus, releases medication for up to 5 years

Each of these progestin-only methods can make your periods lighter and less frequent or stop them altogether. Continuous progestins are safe, effective and well-tolerated by most women. Weight gain, bloating, and depression are sometimes reported. Irregular or unscheduled “breakthrough” bleeding can occur also but usually becomes less frequent the longer you use the medication. You should discuss the pros and cons of continuous progestin-only hormone therapy with your gynecologist to see if one of these methods is right treatment for you.


Danazol is a synthetic androgen (male hormone) which is an effective medical treatment for endometriosis.

  • It is given as a pill 2-4 times daily in doses of 400-800 mg per day
  • It works by making the active endometriosis implants “inactive” or atrophic so they do not grow
  • When endometriosis implants become inactive pelvic pain often decreases.
  • Danazol also lowers estrogen levels which is helpful in the treatment of endometriosis.
  • Danazol may be prescribed for other uses such as fibrocystic breast disease.

Side effects may include:

  • Changes in the menstrual cycle; no periods, irregular periods or spotting
  • Mild weight gain
  • Bloating
  • Some women will experience androgenic (male hormone) side effects including hair growth, acne, oily skin and/or oily hair. All of these side effects are reversible when the medication is stopped however; it may take up to 6-9 months for the effects to resolve completely.
  • Irritability and/or nervousness
  • A rare but non-reversible side effect is deepening of the voice

Rare side effects may include pressure in the brain, including stroke, liver disease and bleeding in the abdomen.

Before taking Danazol:

  • It is very important to tell your doctor if you are taking other prescription or nonprescription medicines including herbs and vitamins.
  • Be sure to tell your doctor if you suffer from migraine headaches; heart, kidney, liver disease or if you have ever had a seizure.


  • Danazol should not be taken if you are pregnant or breastfeeding
  • A non-hormonal type of birth control to prevent pregnancy must be used if you are sexually active.
  • If you become pregnant while taking Danazol, call your doctor right away.

Lupron® with Add-back

Another highly effective way to treat endometriosis is to lower the natural estrogen levels altogether by giving an injectable medication, called leuprolide acetate (Lupron®). This medication is given as a shot every 1 or 3 months depending on the dose. When given continuously, Lupron® turns off the chain of hormonal signals that tell the ovaries to make estrogen. This stops your menstrual period and lowers estrogen levels to a point where endometriosis becomes inactive.

Similar to continuous hormonal therapies, Lupron® can be associated with irregular bleeding at first but usually results in cessation of periods over time. Women should know that they may have a “flare up” of symptoms shortly after they receive their first dose of medication because estrogen levels usually increase for days to weeks before they fall, causing a temporary menopause-like condition. Later, low estrogen levels may contribute to hot flashes (episodes of feeling suddenly hot, flushed, and sweaty), mood changes, vaginal dryness, and other symptoms that are typically associated with menopause. Over time, low estrogen levels may lead to low bone mineral density and possibly fragile bones that are at greater risk for fracture.

However, there is a way to get the most benefit from Lupron® with minimal or no side effects. We always prescribe low-dose hormonal “add-back” medication such as daily Aygestin (see medical treatments: continuous progestin) or a combined estrogen/progestin add-back regimen, along with Lupron®. Add-back therapy offsets the side effects of Lupron® which results in a high degree of patient satisfaction while still suppressing endometriosis. Your doctor may monitor your bone mineral density with a DXA scan if you have been on Lupron for 6 months or longer. We do not recommend Lupron® for females less than 16 years of age. Talk to your gynecologist about whether Lupron® with add-back therapy is the right treatment for you.

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