The injectable drug leuprorelin (Lupron) may help temporarily ease endometriosis symptoms in people who find that other treatments are providing no relief.

Lupron is a common brand name for leuprorelin. Other brand names include Eligard and Lucrin.

The drug can cause intense side effects in some people. Because it also reduces estrogen levels, Lupron causes the body to enter a state similar to menopause.

People considering Lupron should carefully weigh the risks and possible benefits. Below, learn more about Lupron as a treatment for endometriosis, including the possible side effects.

What is Lupron?

Lupron may help relieve the symptoms of endometriosis.
Lupron, or leuprorelin, is a gonadotropin-releasing hormone (GnRH) agonist. This means that it changes the way the pituitary gland behaves, reducing the production of certain hormones, including estrogen and testosterone.

Researchers originally developed leuprorelin as a drug to treat prostate cancer.

In people with endometriosis, Lupron causes the body to enter a state similar to menopause. Menstruation stops and estrogen withdrawal symptoms, such as hot flashes, tend to develop.

As endometriosis is an estrogen-dependent condition, some symptoms of endometriosis may improve or disappear along with these changes. For example, as periods stop, so may the heavy bleeding and pain that endometriosis can cause during menstruation.

Side effects and risks
Lupron lowers estrogen levels in the body, typically triggering menopause-like symptoms.

According to the manufacturer’s clinical trials, 74% of participants who took Lupron stopped having their periods after the first month of treatment, and menstruation ceased in 98% of this group after 2 months.

After stopping Lupron treatment, most people find that menstruation resumes regularly within 3 months.

In people who take Lupron for endometriosis, the drug can cause additional side effects, including:

acne
swelling and fluid retention
night sweats and hot flashes
breast pain and tenderness
joint pain
body aches
headaches
reduced sex drive
anxiety
depression
mood swings
nausea and vomiting
loss of bone density
Because of the possible effects on bone density, experts recommend not taking Lupron to treat endometriosis for longer than 6 months.

If endometriosis symptoms persist, the doctor may recommend repeating treatment for 6 months in combination with a hormone replacement drug called norethindrone acetate. Some bone density loss may not be reversible.

In 2017, the Food and Drug Administration (FDA) announced an investigation into reports of severe adverse effects to assess the need for further regulation.

People should also be aware that, in addition to potentially causing depression as a side effect, Lupron can make existing depression symptoms worse.

The FDA classify Lupron as pregnancy risk category X. This means that research indicates that the drug may harm a developing fetus, possibly causing a wide range of congenital abnormalities.

Pregnant women and those who are trying to become pregnant should not use this drug.

Is it effective?
Clinical trials of Lupron have found that it can reduce the following endometriosis symptoms:

pelvic pain
painful periods
pain during sex
Research also indicates that taking the drug leads to a reduction in the size of the implanted tissue that characterizes endometriosis.

Procedure
The standard dosage of Lupron for endometriosis is an intramuscular injection every month. Each shot contains 3.75 mg of the drug.

In most cases, a doctor or nurse administers the injection in a clinic. A person’s treatment may involve an injection of Lupron alone or in combination with norethindrone acetate, a hormone replacement.

Because of its side effects, it is best to use Lupron for the shortest possible period.

A doctor may recommend taking Lupron for several months before having surgery to reduce the size of the endometriosis implants.

Some women with endometriosis use Lupron to improve their chances of a successful pregnancy. They may take Lupron for several months to reduce endometriosis symptoms, then start trying for a pregnancy.

Also, some fertility clinics use Lupron on an off-label basis to suppress the natural hormonal cycle before beginning treatment with in vitro fertilization, or IVF.

In addition, doctors may prescribe Lupron to treat conditions such as prostate cancer and uterine fibroids.

Lupron vs. Zoladex
Like Lupron, goserelin (Zoladex) is a GnRH agonist that suppresses estrogen production.

Both injectable drugs induce a reversible menopause-like state, and the two drugs seem to have similar effects on endometriosis.

While there is no clinical evidence that either drug is more effective, some individuals have better results — and fewer side effects — from taking either Lupron or Zoladex.

Physical responses to the drugs’ formulas can vary. It is key to discuss the decision with a doctor, who can describe the specific risks and advise about each drug’s suitability.

Alternatives
GnRH drugs such as Lupron and Zoladex are not the only treatment options for endometriosis. Because of the side effects that these medications can cause, most doctors recommend other treatments first.

Alternatives include:

Pain medication. Over-the-counter nonsteroidal anti-inflammatory drugs, such as ibuprofen, can help ease pain from endometriosis. Some people also use prescription pain relievers.
Combined oral contraceptives. These birth control pills can help regulate the menstrual cycle and reduce heavy bleeding.
Progesterone treatments. Progesterone is a hormone that can lighten or stop menstrual bleeding. It is available in pills, injections, and intrauterine devices, or IUDs.
Surgery. A doctor may recommend surgery to remove endometriosis implants, break up scar tissue, improve fertility, and reduce pain.
Summary
While there is no cure for endometriosis, the right treatment can manage symptoms and reduce the risk of complications.

Lupron may offer relief, especially to women who have found other treatments to be ineffective and who do not wish to become pregnant right away.

There is a range of treatment options, and it is important to discuss endometriosis symptoms, side effects, and treatment goals with a healthcare provider.