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Myfembree Side Effects

Generic name: estradiol / norethindrone / relugolix

Medically reviewed by Philip Thornton, DipPharm. Last updated on May 28, 2022.

Note: This document contains side effect information about estradiol / norethindrone / relugolix. Some dosage forms listed on this page may not apply to the brand name Myfembree.

Applies to estradiol / norethindrone / relugolix: oral tablet.


Oral route (Tablet)

Estrogen and progestin combination products, including relugolix/estradiol/norethindrone acetate, increase the risk of thrombotic or thromboembolic disorders including pulmonary embolism (PE), deep vein thrombosis (DVT), stroke and myocardial infarction (MI), especially in women at increased risk for these events. Relugolix/estradiol/norethindrone acetate is contraindicated in women with current or a history of thrombotic or thromboembolic disorders and in women at increased risk for these events, including women over 35 years of age who smoke or women with uncontrolled hypertension.

Serious side effects of Myfembree

Along with its needed effects, estradiol / norethindrone / relugolix may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking estradiol / norethindrone / relugolix:

More common

  • Heavy non-menstrual vaginal bleeding
  • longer or heavier menstrual periods
  • normal menstrual bleeding occurring earlier, possibly lasting longer than expected
  • unusually heavy or unexpected menstrual bleeding
  • vaginal bleeding or spotting

Less common

  • Anxiety
  • discouragement
  • feeling sad or empty
  • hair loss, thinning of hair
  • irritability
  • lack of appetite
  • loss of interest or pleasure
  • mood swings
  • trouble concentrating
  • trouble sleeping
  • unusual tiredness or weakness


Incidence not known

Other side effects of Myfembree

Some side effects of estradiol / norethindrone / relugolix may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common

  • Feeling of warmth
  • increased sweating
  • night sweats
  • redness of the face, neck, arms, and occasionally, upper chest
  • toothache

Less common

  • Back pain
  • decreased interest in sexual intercourse
  • difficulty in moving
  • inability to have or keep an erection
  • joint pain
  • loss in sexual ability, desire, drive, or performance
  • muscle pain or stiffness

For Healthcare Professionals

Applies to estradiol / norethindrone / relugolix: oral tablet.


The most common adverse reactions have included hot flush, uterine bleeding, hyperhidrosis, night sweats, alopecia, and decreased libido.[Ref]


Very common (10% or more): Posttherapy resumption of menstruation (up to 100%)

Common (1% to 10%): Uterine bleeding/abnormal uterine bleeding (included menorrhagia, metrorrhagia, vaginal hemorrhage, polymenorrhea, menstruation irregular)

Uncommon (0.1% to 1%): Uterine myoma expulsion, uterine leiomyoma (prolapse), pelvic pain


-Postmarketing reports: Uterine leiomyoma degeneration[Ref]


Very common (10% or more): Decline in lumbar spine bone mineral density (BMD; up to 23%)

Uncommon (0.1% to 1%): Low trauma fractures

Frequency not reported: Bone loss[Ref]

In clinical trials, women treated with this drug for up to 52 weeks had a decline in lumbar spine BMD of 0.8%. A decline in lumbar spine BMD of greater than 3% was observed in 23% (30/132) of women who had a dual-energy x-ray absorptiometry (DXA) scan after 12 months of therapy with this drug and in 17.4% (37/213) of untreated women. A decline of greater than 8% was seen in 0.8% (1/132) of women receiving this drug who completed a DXA scan at 12 months and in 0.9% (2/213) of untreated women.[Ref]


For women with normal total cholesterol (less than 200 mg/dL) at baseline, increases to 200 to 240 mg/dL and increases to greater than 240 mg/dL were seen in 13.7% and 1.7% of patients treated with this drug, respectively. For women with LDL cholesterol less than 130 mg/dL at baseline, increases to 130 to less than 160 mg/dL, 160 to less than 190 mg/dL, and at least 190 mg/dL were seen in 9.3%, 1.5%, and 0.5% of women treated with this drug, respectively.[Ref]

Very common (10% or more): Increased total cholesterol (up to 13.7%)

Common (1% to 10%): Increased low-density lipoprotein (LDL) cholesterol, breast cyst[Ref]


In clinical trials in 1066 women treated with this drug for another indication, 2 thromboembolic events (DVT and PE) occurred in 1 woman with risk factors of obesity and a preceding knee injury; 1 case was reported for a woman treated with relugolix monotherapy in the postmarketing period.[Ref]

Common (1% to 10%): Hot flush, new/worsening hypertension

Rare (0.01% to 0.1%): Thromboembolic events (deep vein thrombosis [DVT], pulmonary embolism [PE])


-Postmarketing reports: Thromboembolic event[Ref]


Common (1% to 10%): Alopecia/hair loss/hair thinning, hyperhidrosis, night sweats


-Postmarketing reports: Drug eruption[Ref]


Common (1% to 10%): Decreased libido (included decreased libido, loss of libido), irritability, depression (included depression, mood swings, depressed mood), anxiety

Frequency not reported: Suicidal ideation, adverse mood changes[Ref]


Common (1% to 10%): Dyspepsia[Ref]


Uncommon (0.1% to 1%): Elevated AST, elevated ALT, cholecystitis[Ref]

In clinical trials, elevated AST (at least 3 times the upper limit of normal [3 x ULN]: 0.8%) and ALT (at least 3 x ULN: 0.4%) occurred in women treated with this drug.[Ref]


Frequency not reported: Anaphylactoid reactions


-Postmarketing reports: Anaphylactoid reaction[Ref]



-Postmarketing reports: Pulmonary embolism[Ref]

Frequently asked questions


1. Cerner Multum, Inc. "UK Summary of Product Characteristics." O 0

2. "Product Information. Myfembree (estradiol / norethindrone / relugolix)." Myovant Sciences, Inc. (2021):

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.