WARNINGS
See BOXED WARNINGS.
Warnings Associated with Estrogens
Cardiovascular Disorders
Estrogen and estrogen/progestin therapy has been associated with an increased risk of cardiovascular events such as myocardial infarction and stroke, as well as venous thrombosis and pulmonary embolism (venous thromboembolism or VTE). Should any of these occur or be suspected, estrogens should be discontinued immediately.
Risk factors for arterial vascular disease (e.g., hypertension, diabetes mellitus, tobacco use, hypercholesterolemia, and obesity) and/or venous thromboembolism (e.g., personal history or family history of VTE, obesity, and systemic lupus erythematosus) should be managed appropriately.
Coronary Heart Disease and Stroke: In the Women's Health Initiative
(WHI) study, an increase in the number of myocardial infarctions and strokes
was observed in women receiving CE compared to placebo. The CE-only substudy
has concluded. The impact of those results are under review. (See CLINICAL
PHARMACOLOGY, Clinical Studies.)
In the CE/MPA substudy of WHI, an increased risk of coronary heart disease (CHD) events (defined as nonfatal myocardial infarction and CHD death) was observed in women receiving CE/MPA compared to women receiving placebo (37 versus 30 per 10,000 women-years). The increase in risk was observed in year 1 and persisted.
In the same substudy of WHI, an increased risk of stroke was observed in women
receiving CE/MPA compared to women receiving placebo (29 versus 21 per 10,000
women-years). The increase in risk was observed after the first year and persisted.
In postmenopausal women with documented heart disease (n = 2,763, average age 66.7 years) a controlled clinical trial of secondary prevention of cardiovascular disease (Heart and Estrogen/Progestin Replacement Study; HERS) treatment with CE/MPA (0.625 mg/2.5 mg per day) demonstrated no cardiovascular benefit. During an average follow-up of 4.1 years, treatment with CE/MPA did not reduce the overall rate of CHD events in postmenopausal women with established coronary heart disease. There were more CHD events in the CE/MPA-treated group than in the placebo group in year 1, but not during the subsequent years. Two thousand three hundred and twenty one women from the original HERS trial agreed to participate in an open-label extension of HERS, HERS II. Average follow-up in HERS II was an additional 2.7 years, for a total of 6.8 years overall. Rates of CHD events were comparable among women in the CE/MPA group and the placebo group in HERS, HERS II, and overall.
Large doses of estrogen (5 mg conjugated estrogens per day), comparable to those used to treat cancer of the prostate and breast, have been shown in a large prospective clinical trial in men to increase the risks of nonfatal myocardial infarction, pulmonary embolism, and thrombophlebitis.
Venous Thromboembolism (VTE.): In the Women's Health Initiative
(WHI) study, an increase in VTE was observed in women receiving CE compared
to placebo. The CE-only substudy has concluded. The impact of those results
are under review. (See CLINICAL PHARMACOLOGY, Clinical
Studies.)
In the CE/MPA substudy of WHI, a 2-fold greater rate of VTE, including deep venous thrombosis and pulmonary embolism, was observed in women receiving CE/MPA compared to women receiving placebo. The rate of VTE was 34 per 10,000 women-years in the CE/MPA group compared to 16 per 10,000 women-years in the placebo group. The increase in VTE risk was observed during the first year and persisted.
If feasible, estrogens should be discontinued at least 4 to 6 weeks before surgery of the type associated with an increased risk of thromboembolism, or during periods of prolonged immobilization.
Malignant Neoplasms
Endometrial Cancer: The use of unopposed estrogens in women with
intact uteri has been associated with an increased risk of endometrial cancer.
The reported endometrial cancer risk among unopposed estrogen users is about
2- to 12-fold greater than in non-users, and appears dependent on duration of
treatment and on estrogen dose. Most studies show no significant increased risk
associated with use of estrogens for less than one year. The greatest risk appears
associated with prolonged use, with increased risks of 15- to 24-fold for 5
to 10 years or more and this risk has been shown to persist for at least 8 to
15 years after estrogen therapy is discontinued.
Clinical surveillance of all women taking estrogen/progestin combinations is important. Adequate diagnostic measures, including endometrial sampling when indicated, should be undertaken to rule out malignancy in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding. There is no evidence that the use of natural estrogens results in a different endometrial risk profile than synthetic estrogens of equivalent estrogen dose. Adding a progestin to estrogen therapy has been shown to reduce the risk of endometrial hyperplasia, which may be a precursor to endometrial cancer.
Breast Cancer: The use of estrogens and progestins by postmenopausal
women has been reported to increase the risk of breast cancer. The most important
randomized clinical trial providing information about this issue is the Women's
Health Initiative (WHI) substudy of CE/MPA. (See CLINICAL PHARMACOLOGY, Clinical
Studies.) The results from observational studies are generally consistent
with those of the WHI clinical trial and report no significant variation in
the risk of breast cancer among different estrogens or progestins, doses, or
routes of administration.
The CE/MPA substudy of WHI reported an increased risk of breast cancer in women who took CE/MPA for a mean follow-up of 5.6 years. Observational studies have also reported an increased risk for estrogen/progestin combination therapy, and a smaller increased risk for estrogen alone therapy, after several years of use. In the WHI trial and from observational studies, the excess risk increased with duration of use. From observational studies, the risk appeared to return to baseline in about five years after stopping treatment. In addition, observational studies suggest that the risk of breast cancer was greater, and became apparent earlier, with estrogen/progestin combination therapy as compared to estrogen alone therapy.
In the CE/MPA substudy, 26% of the women reported prior use of estrogen alone and/or estrogen/progestin combination hormone therapy. After a mean follow-up of 5.6 years during the clinical trial, the overall relative risk of invasive breast cancer was 1.24 (95% confidence interval 1.01-1.54), and the overall absolute risk was 41 versus 33 cases per 10,000 women-years, for CE/MPA compared with placebo. Among women who reported prior use of hormone therapy, the relative risk of invasive breast cancer was 1.86, and the absolute risk was 46 versus 25 cases per 10,000 women-years, for CE/MPA compared with placebo. Among women who reported no prior use of hormone therapy, the relative risk of invasive breast cancer was 1.09, and the absolute risk was 40 versus 36 cases per 10,000 women-years for CE/MPA compared with placebo. In the same substudy, invasive breast cancers were larger and diagnosed at a more advanced stage in the CE/MPA group compared with the placebo group. Metastatic disease was rare with no apparent difference between the two groups. Other prognostic factors such as histologic subtype, grade and hormone receptor status did not differ between the groups.
The use of estrogen plus progestin has been reported to result in an increase in abnormal mammograms requiring further evaluation. All women should receive yearly breast examinations by a healthcare provider and perform monthly breast self-examinations. In addition, mammography examinations should be scheduled based on patient age, risk factors, and prior mammogram results.
Dementia
In the Women's Health Initiative Memory Study (WHIMS), 4,532 generally healthy
postmenopausal women 65 years of age and older were studied, of whom 35% were
70 to 74 years of age and 18% were 75 or older. After an average follow-up of
4 years, 40 women being treated with CE/MPA (1.8%, n = 2,229) and 21 women in
the placebo group (0.9%, n = 2,303) received diagnoses of probable dementia.
The relative risk for CE/MPA versus placebo was 2.05 (95% confidence interval
1.21 - 3.48), and was similar for women with and without histories of menopausal
hormone use before WHIMS. The absolute risk of probable dementia for CE/MPA
versus placebo was 45 versus 22 cases per 10,000 women-years, and the absolute
excess risk for CE/MPA was 23 cases per 10,000 women-years. It is unknown whether
these findings apply to younger postmenopausal women. (See CLINICAL PHARMACOLOGY,
Clinical Studies and PRECAUTIONS, Geriatric
Use.)
The estrogen alone substudy of the Women's Health Initiative Memory Study has concluded. It is unknown whether these findings apply to estrogen alone.
Gallbladder Disease
A 2- to 4-fold increase in the risk of gallbladder disease requiring surgery in postmenopausal women receiving estrogens has been reported.
Glucose Tolerance
A worsening of glucose tolerance has been observed in a significant percentage of patients on estrogen-containing oral contraceptives. For this reason, diabetic patients should be carefully observed while receiving estrogens.
Hypercalcemia
Estrogen administration may lead to severe hypercalcemia in patients with breast cancer and bone metastases. If hypercalcemia occurs, use of the drug should be stopped and appropriate measures taken to reduce the serum calcium level.
Visual Abnormalities
Retinal vascular thrombosis has been reported in patients receiving estrogens. Discontinue medication pending examination if there is sudden partial or complete loss of vision, or a sudden onset of proptosis, diplopia, or migraine. If examination reveals papilledema or retinal vascular lesions, estrogens should be permanently discontinued.
Warnings Associated with Methyltestosterone
In patients with breast cancer, androgen therapy may cause hypercalcemia by stimulating osteolysis. In this case the drug should be discontinued.
Prolonged use of high doses of androgens has been associated with the development
of peliosis hepatis and hepatic neoplasms including hepatocellular carcinoma.
(See PRECAUTIONS -Carcinogenesis (Androgens).) Peliosis hepatis can be
a life-threatening or fatal complication.
Cholestatic hepatitis and jaundice occur with 17-alpha-alkylandrogens at a relatively low dose. If cholestatic hepatitis with jaundice appears or if liver function tests become abnormal, the androgen should be discontinued and the etiology should be determined. Drug-induced jaundice is reversible when the medication is discontinued.
Edema with or without heart failure may be a serious complication in patients with preexisting cardiac, renal, or hepatic disease. In addition to discontinuation of the drug, diuretic therapy may be required.