Conjugated estrogens and Norethindrone interaction
Conjugated estrogens and Norethindrone: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Conjugated estrogens (Premarin) label · effective 2025-05-30
Adding a progestin to estrogen therapy has been shown to reduce the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer.
Estrogens with or without progestins should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman.
Estrogen Plus Progestin Therapy Cardiovascular Disorders and Probable Dementia Estrogen plus progestin therapy should not be used for the prevention of cardiovascular disease or dementia.
(See CLINICAL STUDIES and WARNINGS, Cardiovascular disorders and Probable Dementia .) The WHI estrogen plus progestin substudy reported increased risks of DVT, pulmonary embolism (PE), stroke and myocardial infarction (MI) in postmenopausal women (50 to 79 years of age) during 5.6 years of treatment with daily oral CE (0.625 mg) combined with medroxyprogesterone…
(See CLINICAL STUDIES and WARNINGS, Cardiovascular disorders .) The WHIMS estrogen plus progestin ancillary study of the WHI reported an increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 4 years of treatment with daily CE (0.625 mg) combined with MPA (2.5 mg), relative to placebo.
From the Norethindrone (Nora BE) label · effective 2024-04-02
CONTRAINDICATIONS Progestin-only oral contraceptives (POPs) should not be used by women who currently have the following conditions: Known or suspected pregnancy Known or suspected carcinoma of the breast Undiagnosed abnormal genital bleeding Hypersensitivity to any component of this product Benign or malignant liver tumors Acute liver disease
Nora-BE does not contain estrogen and, therefore, this insert does not discuss the serious health risks that have been associated with the estrogen component of combined oral contraceptives.
The health care provider is referred to the prescribing information of combined oral contraceptives for a discussion of those risks, including, but not limited to, an increased risk of serious cardiovascular disease in women who smoke, carcinoma of the breast and reproductive organs, hepatic neoplasia, and changes in carbohydrate and lipid metabolism.
The relationship between progestin-only oral contraceptives and these risks have not been established and there are no studies definitely linking progestin-only pill (POP) use to an increased risk of heart attack or stroke.
Some epidemiologic studies of oral contraceptive users have reported an increased relative risk of developing breast cancer, particularly at a younger age and apparently related to duration of use.
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Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.