How does this medication work? What will it do for me?

Ulipristal belongs to the class of medications called selective progesterone receptor modulators. It is used to treat moderate-to-severe signs and symptoms of uterine fibroids in adult women who are in their child-bearing years.

Symptoms of uterine fibroids include heavy menstrual bleeding, anemia, and pelvic pain or pressure. It works by blocking the effect of progesterone on the endometrium (lining of the uterus) while keeping estrogen levels in the normal range. Progesterone is responsible for the development and growth of fibroids, and by blocking this hormone, ulipristal causes fibroids to shrink and become less painful. Heavy menstrual bleeding usually stops within days of starting this medication.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are taking this medication, speak to your doctor. Do not stop taking this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to take this medication if their doctor has not prescribed it.

What form(s) does this medication come in?

Fibristal is no longer being manufactured for sale in Canada. For brands that may still be available, search under ulipristal. This article is being kept available for reference purposes only. If you are using this medication, speak with your doctor or pharmacist for information about your treatment options.

How should I use this medication?

The usual adult dose of ulipristal is 5 mg taken once daily for a 3-month treatment course. The first tablet is taken at any point during the first 7 days of your menstrual period and continued once daily for 90 days. After finishing a treatment course of 3 months, you should wait to have 1 full menstrual cycle where you are not taking any medication before starting a second treatment course. The second treatment course can be started within the first 7 days of your next menstrual period.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are taking the medication without consulting your doctor.

This medication may be taken with food or on an empty stomach.

It is important that this medication be taken exactly as prescribed by your doctor. If you miss a dose, take it as soon as possible and continue with your regular schedule. If it is almost time for your next dose, skip the missed dose and continue with your regular dosing schedule. Do not take a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from light and moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take ulipristal if you:

  • are allergic to ulipristal or any ingredients of the medication
  • are pregnant
  • are breast-feeding
  • have genital bleeding that is undiagnosed or caused by a condition other than uterine fibroids
  • have uterine, cervical, ovarian or breast cancer
  • have a history of liver disease or active liver disease (determined by increased liver function enzymes in blood tests)

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

  • acne
  • constipation
  • fatigue
  • hair loss
  • headache
  • hot flushes
  • endometrial thickening
  • nausea
  • obesity
  • sensation of spinning
  • vaginal discharge

Although most of the side effects listed below don't happen very often, they could lead to serious problems if you do not seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

  • abnormal or heavy uterine bleeding that is worsening
  • breast pain or discomfort
  • new uterine fibroids
  • ovarian cysts (bloating, belly pain, pain during intercourse, pain in the lower back or thighs)
  • pelvic pain
  • signs of liver problems (e.g., nausea, vomiting, diarrhea, loss of appetite, weight loss, yellowing of the skin or whites of the eyes, dark urine, pale stools)
  • worsening fibroid symptoms

Stop taking the medication and seek immediate medical attention if any of the following occur:

  • signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.


January 11, 2019

Health Canada has issued new restrictions concerning the use of ulipristal. To read the full Health Canada Advisory, visit Health Canada's web site at

Asthma: If you have uncontrolled asthma, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Birth control: Effective birth control should be practiced while using this medication as this medication may harm the baby if used during pregnancy. Birth control pills may be affected by ulipristal. For this reason, a different method of birth control, such as condoms or a diaphragm should be used. If you become pregnant while taking this medication, contact your doctor immediately.

Liver function: Liver disease or reduced liver function may cause this medication to build up in the body, causing side effects. If you have liver problems, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. Your doctor may want to test your liver function regularly with blood tests while you are taking this medication.

Ulipristal may cause serious liver damage and in rare cases has led to the need for liver transplant. If you experience symptoms of liver problems such as fatigue, feeling unwell, loss of appetite, nausea, yellowing of the skin or whites of the eyes, dark urine, pale stools, abdominal pain or swelling, and itchy skin, contact your doctor immediately

Menstrual changes: Ulipristal usually causes a decrease in menstrual bleeding and may cause menstrual bleeding to stop altogether while you are taking this medication. If heavy bleeding continues beyond 10 days of treatment with this medication, contact your doctor. Menstrual periods usually return within 4 weeks of stopping this medication.

Thickened endometrium: Ulipristal may cause an increase in the thickness of the lining of the uterus (endometrium). Although this thickening usually goes away within several months of stopping treatment, occasionally, it may continue. Your doctor may recommend an ultrasound of your uterus to monitor for any changes.

Pregnancy: If you take ulipristal while pregnant, it may cause harm to the developing baby. Do not take this medication if you are pregnant or not using effective birth control. If you become pregnant while taking this medication, contact your doctor immediately.

Breast-feeding: It is not known if ulipristal passes into breast milk. If you are a breast-feeding mother and are taking this medication, it may affect your baby. Talk to your doctor about whether you should continue breast-feeding.

Children: The safety and effectiveness of using this medication have not been established for children.

Seniors: The safety and effectiveness of using this medication have not been established for adults over the age of 65.

What other drugs could interact with this medication?

There may be an interaction between ulipristal and any of the following:

  • aprepitant
  • "azole" antifungals (e.g., fluconazole, itraconazole, ketoconazole, voriconazole)
  • barbiturates (e.g., pentobarbital, phenobarbital)
  • birth control pills
  • bosentan
  • cobicistat
  • conivaptan
  • deferasirox
  • diltiazem
  • dronedarone
  • grapefruit juice
  • HIV non-nucleoside reverse transcriptase inhibitors (NNRTIs; e.g., efavirenz, etravirine, nevirapine)
  • HIV protease inhibitors (e.g., atazanavir, indinavir, ritonavir, saquinavir)
  • lumacaftor and ivacaftor
  • macrolide antibiotics (e.g., clarithromycin, erythromycin)
  • mifepristone
  • mitotane
  • modafinil
  • progestins (e.g., cyproterone, levonorgestrel, medroxyprogesterone, megestrol)
  • protein kinase inhibitors (e.g., crizotinib, dabrafenib, imatinib, nilotinib)
  • rifabutin
  • rifampin
  • St. John's wort
  • sarilumab
  • seizure medications (e.g., carbamazepine, levetiracetam, oxcarbazepine, phenytoin, primidone, topiramate)
  • siltuximab
  • tocilizumab
  • verapamil

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

  • stop taking one of the medications,
  • change one of the medications to another,
  • change how you are taking one or both of the medications, or
  • leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.

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