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Name: Premarin

Pregnancy Category X

Drug classes

  • Hormone
  • Estrogen

Therapeutic actions

Estrogens are endogenous female sex hormones important in the development of the female reproductive system and secondary sex characteristics. They affect the release of pituitary gonadotropins; cause capillary dilatation, fluid retention, protein anabolism, and thin cervical mucus; conserve calcium and phosphorus; encourage bone formation; inhibit ovulation and prevent postpartum breast discomfort. They are responsible for the proliferation of the endometrium; absence or decline of estrogen produces signs and symptoms of menopause on the uterus, vagina, breasts, cervix. Their efficacy as palliation in male patients with androgen-dependent prostatic carcinoma is attributable to their competition with androgens for receptor sites, thus decreasing the influence of androgens.


  • Oral: palliation of moderate to severe vasomotor symptoms, atrophic vaginitis, or kraurosis vulvae associated with menopause
  • Treatment of female hypogonadism; female castration; primary ovarian failure
  • Osteoporosis: to retard progression
  • Palliation of inoperable prostatic cancer
  • Palliation of mammary cancer
  • Prevention of postpartum breast engorgement
  • Unlabeled use: postcoital contraceptive
  • Parenteral: treatment of uterine bleeding due to hormonal imbalance in the absence of organic pathology
  • Vaginal cream: treatment of atrophic vaginitis and kraurosis vulvae associated with menopause


Contraindicated in the presence of allergy to estrogens, breast cancer (except in specific, selected patients), estrogen-dependent neoplasm, undiagnosed abnormal genital bleeding, active thrombophlebitis or thromboembolic disorders or history of such from previous estrogen use,
pregnancy (associated with serious fetal defects; women of childbearing age should be advised of the potential risks and birth control measures suggested).

Use caution in the presence of metabolic bone disease, renal insufficiency, CHF, lactation.

Adverse effects

  • CNS: Steepening of the corneal curvature with a resultant change in visual acuity and intolerance to contact lenses, headache, migraine, dizziness, mental depression, chorea, convulsions
  • GI: Gallbladder disease (in postmenopausal women), hepatic adenoma, nausea, vomiting, abdominal cramps, bloating, cholestatic jaundice, colitis, acute pancreatitis
  • CV: Increased blood pressure, thromboembolic and thrombotic disease
  • Hematologic: Hypercalcemia, decreased glucose tolerance
  • GU: Increased risk of endometrial cancer in postmenopausal women, breakthrough bleeding, change in menstrual flow, dysmenorrhea, premenstrual-like syndrome, amenorrhea, vaginal candidiasis, cystitis-like syndrome, endometrial cystic hyperplasia
  • Dermatologic: Photosensitivity, peripheral edema, chloasma, erythema nodosum or multiforme, hemorrhagic eruption, loss of scalp hair, hirsutism, urticaria, dermatitis
  • Local: Pain at injection site, sterile abscess, postinjection flare
  • Other: Weight changes, reduced carbohydrate tolerance, aggravation of porphyria, edema, changes in libido, breast tenderness

Topical Vaginal Cream

  • Systemic absorption may cause uterine bleeding in menopausal women and may cause serious bleeding of remaining endometrial foci in sterilized women with endometriosis.

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