Important Safety Information: hormone therapy
This page summarizes the most important safety information in the FDA prescribing information (labels) for menopausal hormone therapy: estrogen, alone or with a progestogen such as progesterone. It does not include everything in the labels. If a licensed provider prescribes hormone therapy for you, read the patient information that comes with your prescription.
Boxed warnings after the 2025 and 2026 label changes
In November 2025 FDA asked the makers of menopausal hormone therapy to change their labels, and updated labels have been approved since. Under the change, the boxed warning no longer covers cardiovascular disease, breast cancer or probable dementia. For estrogen-alone products that act throughout the body, the boxed warning about endometrial cancer stays.
What the labels we checked on November 1, 2026 show:
- An updated estrogen-alone label carries one boxed warning: an increased risk of endometrial cancer in a woman with a uterus who uses estrogen without a progestogen. Adding a progestogen has been shown to reduce the risk of endometrial hyperplasia, which may come before cancer.
- An updated progesterone label and an updated label for a low-dose estrogen used in the vagina have no boxed warning.
- Some products still carry the older, longer boxed warning while labels are updated. Read the label that comes with your own prescription.
The warnings about heart disease, stroke, blood clots and breast cancer remain in the body of the labels. Risks were not removed; FDA moved them out of the boxed warning.
These label changes cover FDA-approved products. Compounded hormones have no prescribing information approved by FDA, and the changes do not apply to them. Compounded medications are not FDA-approved, and FDA does not review them for safety, effectiveness, or quality before they are marketed.
Who should not use estrogen
The labels list these contraindications:
- vaginal bleeding without a known cause;
- breast cancer now or in the past, or another estrogen-dependent cancer;
- a blood clot in the legs or lungs now or in the past;
- a stroke or heart attack now or in the past;
- liver disease;
- a known clotting disorder, such as protein C, protein S or antithrombin deficiency;
- a severe allergic reaction to the product.
Progesterone is not for people with a known, suspected or past breast cancer, unexplained vaginal bleeding, blood clots, stroke or heart attack, or liver disease. Some progesterone products contain peanut oil and are not for people allergic to peanuts.
Serious risks
- Stroke and blood clots: estrogen-alone therapy increased the risk of stroke and blood clots in the legs and lungs in the Women's Health Initiative (WHI) trials, and estrogen plus progestin increased the risk of stroke, blood clots and heart attack. The labels say to stop treatment right away if one of these occurs or is suspected, and, where possible, to stop 4 to 6 weeks before surgery that carries a higher clot risk or during long periods of immobility.
- Endometrial cancer: for a woman with a uterus, estrogen alone increases this risk. Abnormal bleeding during treatment needs to be checked.
- Breast cancer: in the WHI trial, estrogen plus progestin increased the risk of invasive breast cancer. The labels recommend regular breast exams and mammograms. Estrogen use can lead to more abnormal mammograms that need further evaluation.
- Dementia: in WHI memory studies of women 65 to 79, estrogen alone increased the risk of probable dementia. The updated labels report this finding in the geriatric-use and clinical-studies sections; it is unknown whether it applies to younger women.
- Other risks named in the labels: gallbladder disease, very high calcium, very high triglycerides, yellowing of the skin (cholestatic jaundice), loss of vision, and changes in thyroid medicine needs. The labels say to stop estrogen if severe high calcium, loss of vision, severe high triglycerides or cholestatic jaundice occurs.
The labels state that hormone therapy should not be used to prevent heart disease or dementia.
Common side effects
The most common side effects listed in an updated estradiol label are irregular vaginal bleeding, breast tenderness, vaginal yeast infections and cold-like symptoms. Tell your provider about side effects that bother you or do not go away.
What gets checked
Your provider reviews your history, blood pressure, breast screening and any bleeding before and during treatment, and decides how often to follow up. Tell your provider if you take thyroid medicine, because estrogen can change how much you need.
When to get medical help right away
The labels list warning signs that need a call to your provider right away: new breast lumps, unusual vaginal bleeding, changes in vision or speech, sudden new severe headaches, severe pain in your chest or legs with or without shortness of breath, weakness and fatigue, and swelling of the face, lips or tongue. If symptoms are severe or sudden, call 911.
You can report side effects to FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
Who decides
A licensed provider reviews your symptoms, history and labs and decides, with your input, whether hormone therapy is appropriate for you.
Prescription treatment requires an evaluation by a licensed healthcare provider, who decides whether treatment is appropriate for you. Not everyone qualifies. Completing an assessment, booking a visit, or paying a fee does not guarantee a prescription.