Short answer: In four placebo-controlled trials, the most common Duavee side effects were muscle spasms (9% vs 6% on placebo), nausea (8% vs 5%), diarrhea (8% vs 5%), dyspepsia, upper abdominal pain, throat pain, dizziness and neck pain. Stopping because of side effects was 7.5% on Duavee vs 10.0% on placebo. The boxed warning covers endometrial cancer, stroke and blood clots, and probable dementia.
What Duavee is approved for: Duavee combines conjugated estrogens with bazedoxifene, an estrogen agonist/antagonist. It is approved for women with a uterus to treat moderate to severe hot flashes (vasomotor symptoms) of menopause and to prevent postmenopausal osteoporosis (sections 1.1, 1.2). The bazedoxifene part lowers the risk of endometrial hyperplasia from the estrogen part, so no progestin is added (section 5.3).
Source
DUAVEE (conjugated estrogens/bazedoxifene) tablets, for oral use, prescribing information and Patient Information. Wyeth Pharmaceuticals (Pfizer). DailyMed, version published April 29, 2026. DailyMed setid e1b75458-2e5b-46b9-92c6-fa6daba3770f
WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, AND PROBABLE DEMENTIA
Women taking Duavee do not take additional estrogens. A woman with a uterus who uses estrogen alone has a higher risk of endometrial cancer; Duavee has been shown to reduce the risk of endometrial hyperplasia, a possible precursor. Undiagnosed, persistent or recurring abnormal genital bleeding after menopause is checked, including with endometrial sampling when indicated. Estrogen is not used to prevent heart disease or dementia. In the Women's Health Initiative (WHI), daily oral conjugated estrogens 0.625 mg alone raised the risk of stroke and deep vein thrombosis in women 50 to 79 over 7.1 years, and the WHI Memory Study found a higher risk of probable dementia in women 65 and older over 5.2 years. Only that dose was studied, so how the findings apply to other doses or products is not known. Estrogens are prescribed at the lowest effective dose for the shortest duration consistent with treatment goals and risks.
These are the label's own numbers from the Adverse Reactions section. Where the label compares with placebo (a dummy treatment), both columns are shown, so you can see how much more often a reaction happened on Duavee.
| Adverse reaction | Duavee (N=1224) | Placebo (N=1069) |
|---|---|---|
| Nausea | 100 (8) | 58 (5) |
| Diarrhea | 96 (8) | 57 (5) |
| Dyspepsia | 84 (7) | 59 (6) |
| Abdominal pain upper | 81 (7) | 58 (5) |
| Muscle spasms | 110 (9) | 63 (6) |
| Neck pain | 62 (5) | 46 (4) |
| Dizziness | 65 (5) | 37 (3) |
| Oropharyngeal pain | 80 (7) | 61 (6) |
Four Phase 3 trials of 12 weeks to 24 months in postmenopausal women 40 to 75. Values are number of women (percent). All-cause deaths were 0.0% on Duavee vs 0.2% on placebo; serious adverse reactions 3.5% vs 4.8%.
Stopping because of adverse reactions was 7.5% on Duavee vs 10.0% on placebo. The most common reasons were hot flush, upper abdominal pain and nausea.
Venous thromboembolism (DVT, pulmonary embolism, retinal vein thrombosis) was reported in 0.0% on Duavee and 0.1% on placebo. The label says the rates were too low to conclude the risk differs from other estrogen therapies.
WHI estrogen alone (oral CE 0.625 mg): stroke 45 vs 33 per 10,000 women-years on placebo; blood clots (VTE) 30 vs 22, with DVT 23 vs 15. In women 50 to 59, stroke was 18 vs 21.
Endometrial cancer risk with estrogen alone in a woman with a uterus is about 2 to 12 times that of non-users, and 15 to 24 times with 5 to 10 years or more of use. The effect of Duavee on breast and ovarian cancer risk is unknown.
WHIMS estrogen alone, women 65 to 79: probable dementia 37 vs 25 per 10,000 women-years (relative risk 1.49).
Women with liver impairment taking bazedoxifene alone had on average a 4.3-fold higher exposure than controls.
The Warnings and Precautions part of the label lists these. Each line gives the label's heading and what it means in plain words.
Who should not use it. Women with undiagnosed abnormal uterine bleeding, known, suspected or past breast cancer, estrogen-dependent cancer, current or past blood clots, stroke or heart attack, allergy to estrogens, bazedoxifene or the ingredients, liver impairment or disease, protein C, protein S or antithrombin deficiency or other clotting disorders, or pregnancy.
No added hormones. Women taking Duavee do not take progestins, additional estrogens or additional estrogen agonist/antagonists. Extra estrogen may raise the risk of endometrial hyperplasia (section 5.3).
Stroke and blood clots. Bazedoxifene and estrogens are each known to raise blood clot risk. Duavee is stopped right away if a stroke or clot occurs or is suspected, stopped 4 to 6 weeks before high-risk surgery if feasible and during long immobilization, and restarted only once fully mobile. Moving about during long travel is advised.
Endometrial, breast and ovarian cancer. Abnormal bleeding is checked for cancer. Yearly breast exams by a provider and monthly self-exams are advised. A meta-analysis linked current hormone therapy to ovarian cancer (relative risk 1.41); Duavee's own effect on breast and ovarian cancer is unknown.
Probable dementia. WHIMS found a higher risk of probable dementia in women 65 to 79 on oral estrogen alone. Whether this applies to younger women is unknown.
Gallbladder disease. A 2- to 4-fold rise in gallbladder disease needing surgery has been reported in postmenopausal women taking estrogens.
Vision problems. Blood clots in the retina have been reported with estrogens. Duavee is stopped pending exam for sudden vision loss, bulging eyes, double vision or migraine, and permanently if papilledema or retinal vessel lesions are found.
Triglycerides, thyroid and other conditions. In women with high triglycerides, estrogen can raise them and cause pancreatitis (5.8). Women on thyroid hormone may need higher doses (5.10). Estrogen can cause fluid retention and may worsen asthma, diabetes, epilepsy, migraine, porphyria, lupus, liver hemangiomas and hereditary angioedema (5.11 to 5.14).
Premenopausal women. Duavee is not indicated or recommended before menopause, and there is concern about exposure in pregnancy because of possible harm to a fetus.
From the Patient Information that comes with Duavee:
Dose Track has a side-effect log. Each entry records the symptom, a severity (none, mild, moderate, severe or life-threatening), the date and an optional note, and can be tied to a specific dose or logged on its own. The history screen shows what you logged over time, which makes it easier to tell your prescriber when a reaction started and whether it is easing. The app records what you enter; it does not judge whether a symptom is serious. For anything on the label's call-your-doctor list, call your doctor.
This page is what the FDA label says, in plain words. It is not medical advice. Follow your prescriber, and ask them or your pharmacist about anything here.