Side Effects of Orilissa: What You Need to Know

Orilissa (elagolix) is a prescription drug used to treat moderate to severe pain from endometriosis. Orilissa can cause side effects that range from mild to serious. Examples include hot flashes, headache, and weight gain.

Orilissa is used in adults to treat moderate to severe pain from endometriosis.

Orilissa comes as a tablet that you swallow. It contains the active ingredient elagolix. (An active ingredient is what makes a drug work.)

Keep reading to learn about the common, mild, and serious side effects that Orilissa can cause. For a general overview of the drug, including details about its uses, see this article.

Some people may experience mild to serious side effects while taking Orilissa. Examples of the drug’s commonly reported side effects include:

• night sweats
• headache
• nausea
• insomnia (trouble sleeping)
• hot flashes*

* To learn more about this side effect, see the “Side effects explained” section below.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you’d like to notify the FDA about a side effect you’ve had with Orilissa, visit MedWatch.

Mild side effects have been reported with Orilissa. Examples include:

• sweating during the night
• headache
• nausea
• insomnia (trouble sleeping)
• joint pain
• low sex drive
• diarrhea
• belly pain
• dizziness
• constipation
• irritability
• changes in period length and intensity
• hot flashes*
• amenorrhea (loss of menstrual periods)*
• weight gain*
• mild allergic reaction*

* To learn more about this side effect, see the “Side effects explained” section below.

In most cases, these side effects should be temporary. And some may be easily managed. But if you have symptoms that are ongoing or bother you, talk with your doctor or pharmacist. And do not stop taking Orilissa unless your doctor recommends it.

Orilissa may cause mild side effects other than those listed above. See the drug’s prescribing information for details.

Serious side effects have been reported with Orilissa but most of them are rare. These include:

• liver problems
• bone loss*
• mood changes, including suicidal thoughts and behaviors*
• severe allergic reaction*

* To learn more about this side effect, see the “Side effects explained” section below.

If you develop serious side effects while taking Orilissa, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Help is out there

If you or someone you know is in crisis and considering suicide or self-harm, please seek support:

• Call the 988 Suicide and Crisis Lifeline at 988.
• Text HOME to the Crisis Textline at 741741.
• Not in the United States? Find a helpline in your country with Befrienders Worldwide.
• Call 911 or your local emergency services number if you feel safe to do so.

If you’re calling on behalf of someone else, stay with them until help arrives. You may remove weapons or substances that can cause harm if you can do so safely.

If you are not in the same household, stay on the phone with them until help arrives.

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Get answers to some frequently asked questions about Orilissa’s side effects.

Are there reviews of side effects from Orilissa?

Reviews of side effects from Orilissa on the manufacturer’s website don’t discuss specific side effects people experience. The reviews highlight that Orilissa is a drug that can work for some people. They recommend speaking with your doctor or gynecologist about any side effects you may have or are concerned about having.

How long do side effects of Orilissa last?

How long side effects of Orilissa last depends on the side effect. Mild side effects are temporary and should clear over time. But bone loss, for example, is a side effect that can persist even after you stop taking Orilissa.

Over the course of your treatment, this drug may change your periods, so you might have trouble knowing if you’re pregnant. Depression and mood changes may also persist throughout treatment with Orilissa.

If you’re concerned about long-lasting side effects of Orilissa, talk with your doctor or pharmacist. They can help you manage side effects and determine if this is the right treatment for you.

Is weight loss a side effect of Orilissa?

No, weight loss isn’t a reported side effect of Orilissa, but weight gain is. Weight gain isn’t common with this drug, but if you’re concerned about this side effect, talk with your doctor. They can help determine if Orilissa is causing changes in your weight. They can also give you tips on how to achieve and maintain a weight that’s healthy for you.

Can Orilissa cause hair loss?

No, hair loss isn’t a reported side effect of Orilissa. In studies of the drug, changes in hair growth or loss weren’t reported. If you experience hair loss or excessive hair growth while taking Orilissa, talk with your doctor. They can help determine the cause and may be able to recommend a treatment.

Learn more about some of the side effects Orilissa may cause.

Weight gain

Weight gain is possible with Orilissa, but wasn’t a common side effect in the drug’s studies. People who gained weight while taking Orilissa didn’t report how much they gained.

What might help

If you’re concerned about weight gain with Orilissa, talk with your doctor. They can help determine if the drug is causing it. They can also suggest ways to help you achieve and maintain a body weight that’s healthy for you while you’re taking Orilissa. These may include:

• eating healthy foods most of the time
• exercising regularly
• getting enough sleep
• reducing your stress

Mood changes, including suicidal thoughts and behaviors

A rare but serious side effect of Orilissa is mood changes, including suicidal thoughts and behaviors. In studies, people taking this drug had a higher risk of depression and mood changes, such as feeling anxious. And those with a history of depression or suicidal thoughts or behaviors had a higher risk of mood changes with Orilissa.

Some symptoms of depression may include:

• ongoing sad or anxious feelings
• changes in appetite
• ongoing feelings of guilt or worthlessness
• suicide attempts or thoughts of death

What might help

Before starting treatment with Orilissa, tell your doctor if you have a history of mood disorders or depression.

If you experience suicidal thoughts or behaviors, depression, or mood changes while taking Orilissa, call your doctor immediately. They’ll discuss your symptoms with you and determine if Orilissa is still the best treatment for your condition. And they may refer you to a mental health specialist.

But if you have symptoms that feel severe or overwhelming, call 911 or your local emergency number immediately.

Bone loss

Bone loss can occur with Orilissa. In studies, bone loss occurred more often in people who took higher doses of the drug. Those who took Orilissa for a long time also had a higher risk of bone loss. And the bone loss wasn’t always completely reversible.

What might help

If you have a history of bone loss or osteoporosis, tell your doctor before starting treatment with Orilissa. They may order a test to check your bone mineral density before prescribing this drug for you, especially if you have a higher risk for bone loss. If you currently have osteoporosis, they’ll likely not prescribe Orilissa for you. To limit bone loss, doctors usually only prescribe this drug for 6 to 24 months.

The effects of taking calcium and vitamin D to prevent bone loss haven’t been studied. But these supplements may be helpful, so ask your doctor if they recommend you take them.

Hot flashes

Hot flashes were a common side effect of Orilissa in the drug’s studies. Taking a higher dose of Orilissa may increase your risk of this side effect.

Hot flashes feel like excessive heat around the head, neck, chest, and upper back. People with hot flashes may experience flushing (temporary warmth, redness, or deepening of skin color). Sweating may also follow hot flashes.

What might help

Hot flashes were a common reason people stopped taking Orilissa in studies. When you quit taking Orilissa your hot flashes may go away. But you should not stop taking this drug without talking with your doctor first.

Some tips to help with hot flashes include:

• dressing in layers that can be removed when needed
• carrying a portable fan
• avoiding alcohol, spicy foods, and caffeine
• quitting smoking (if you smoke)
• maintaining a weight that’s healthy for you
• meditating or practicing mindfulness

Talk with your doctor if you need help managing hot flashes with Orilissa.

Amenorrhea (loss of menstrual periods)

Another common side effect of Orilissa is the loss of your periods. You may have little to no bleeding when you’re supposed to have your period. This can be a confusing side effect because you may have trouble knowing whether you’re pregnant.

The higher dose of Orilissa is associated with a higher risk of amenorrhea. This is a side effect that can persist throughout your treatment with the drug.

What might help

Orilissa isn’t safe for pregnant people or those trying to become pregnant. Your doctor will recommend you use non-hormonal birth control while taking this drug. If you become pregnant while taking Orilissa, you’ll need to quit taking it. After stopping treatment with Orilissa, your period should come back within about 6 months.

If you’re concerned about how Orilissa will affect your periods, talk with your doctor.

Allergic reaction

Like most drugs, Orilissa can cause an allergic reaction in some people. Symptoms can be mild to serious and can include:

• skin rash
• itchiness
• flushing (temporary warmth, redness, or deepening of skin color)
• swelling under your skin, usually in your eyelids, lips, hands, or feet
• swelling of your mouth, tongue, or throat, which can make it hard to breathe

What might help

If you have mild symptoms of an allergic reaction, such as a mild rash, call your doctor right away. They may suggest a treatment to manage your symptoms. Examples include:

• an antihistamine you swallow, such as Benadryl (diphenhydramine)
• a product you apply to your skin, such as hydrocortisone cream

If your doctor confirms you’ve had a mild allergic reaction to Orilissa, they’ll decide if you should continue taking it.

If you have symptoms of a severe allergic reaction, such as swelling or trouble breathing, call 911 or your local emergency number right away. These symptoms could be life threatening and require immediate medical care.

If your doctor confirms you’ve had a serious allergic reaction to Orilissa, they may have you switch to a different treatment.

• what dose of the drug you were taking when you had the side effect
• how soon you had the side effect after starting that dose
• what your symptoms were
• how your symptoms affected your daily activities
• what other medications you were taking
• any other information you feel is important

Orilissa may not be right for you if you have certain medical conditions. (This is known as a drug-condition interaction.) Other factors may also affect whether this drug is a good treatment option for you. Talk with your doctor about your health history before starting Orilissa. Factors to consider include those described below.

Osteoporosis. Doctors will not prescribe Orilissa for you if you have osteoporosis. This drug can cause bone loss and may make your condition worse. Instead, they can give you information about other treatment options for your condition.

History of bone fracture. If you have risk factors for osteoporosis or a history of bone fractures due to fragile bones, tell your doctor. They’ll likely order a bone mineral density test for you before prescribing this drug. Ask them if taking calcium and vitamin D supplements may be beneficial for you.

Allergic reaction. If you’ve had an allergic reaction to Orilissa or any of its ingredients, your doctor will likely not prescribe this drug for you. Ask them about other medications that might be better options.

Liver problems. If you have severe liver failure, your doctor will likely not prescribe Orilissa for you. Depending on the severity of your liver failure, your doctor may need to adjust your dose and how long you’ll take Orilissa.

History of depression. Orilissa can worsen depression in people with a history of mood disorders such as depression or anxiety. Tell your doctor immediately if you have symptoms of worsening depression or suicidal thoughts or behaviors. Your doctor may refer you to a mental health specialist while you’re taking Orilissa. (For more details, see the “Side effects explained” section above.)

Alcohol and Orilissa

Some medications interact with alcohol, but Orilissa isn’t one of them. Before starting Orilissa, ask your doctor or pharmacist if it’s safe for you to drink alcohol while taking this drug.

Pregnancy and breastfeeding while taking Orilissa

Orilissa is not safe to use during pregnancy. This drug can cause early pregnancy loss when taken early in pregnancy. If you become pregnant while taking Orilissa, tell your doctor immediately.

If you become pregnant during treatment, consider enrolling in Orilissa’s BLOOM Pregnancy Registry by calling 833-782-7241 or visiting the website. Reporting the effects of Orilissa during your pregnancy helps researchers better understand the drug’s effects in pregnant people.

Since Orilissa causes changes in your periods, you might have trouble knowing if you’re pregnant. If you’re uncertain, take a pregnancy test or talk with your doctor.

It’s not known if Orilissa is found in breastmilk or if it affects breastmilk production. There’s also no information on how the drug might affect a child who is breastfed.

If you’re considering breastfeeding while taking Orilissa, talk with your doctor first. They can help you determine if the health benefits of breastfeeding your baby outweigh the possible risks.

Orilissa causes both mild and serious side effects. But they don’t happen to everyone. If you have questions about side effects that Orilissa can cause, talk with your doctor. Examples of questions to help get you started include:

• Does Orilissa cause loss of appetite?
• How do the side effects of Orilissa compare with other drugs, such as hormonal birth control, that are used to treat pain from endometriosis?
• Are the side effects worse if I take Orilissa twice per day?

To get information on different conditions and tips for improving your health, subscribe to any of Austra Health’s newsletters. You may also want to check out the online communities at Bezzy. It’s a place where people with certain conditions can find support and connect with others.

Disclaimer: Austra Health has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.

Last medically reviewed on March 20, 2023