What is Prometrium (progesterone)?

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From the Guidelines

Prometrium is a brand name for oral micronized progesterone, a bioidentical hormone medication that has been shown to have a favorable profile in minimizing hormonal-related cardiovascular risks compared to synthetic progestogens 1. When considering the use of Prometrium, it's essential to understand its benefits and potential side effects. The medication is primarily used to treat menstrual irregularities, prevent endometrial hyperplasia in women taking estrogen, and support early pregnancy in women with progesterone deficiency.

  • The typical dose ranges from 100-200 mg daily, often taken at bedtime to minimize side effects like drowsiness.
  • For menopause hormone therapy, it's commonly prescribed as 100 mg daily for women with an intact uterus who are taking estrogen, or 200 mg daily for 12-14 days per month in cyclic regimens.
  • Prometrium comes in capsules containing peanut oil, so patients with peanut allergies should avoid it. Unlike synthetic progestins, Prometrium is bioidentical to the body's natural progesterone, which may result in fewer side effects and potentially lower cardiovascular risks, as demonstrated by recent studies 1.
  • Common side effects include drowsiness, dizziness, and headaches, which is why it's often recommended to be taken at night. The European Society for Human Reproduction and Embryology (ESHRE) has included micronized progesterone, the active ingredient in Prometrium, among the recommended progestogens in HRT in adult women with ovarian insufficiency, due to its safer pharmacological profile 1.

From the FDA Drug Label

Progesterone capsules contain the female hormone called progesterone. Progesterone capsules are used for the treatment of secondary amenorrhea (absence of menstrual periods in women who have previously had a menstrual period) due to a decrease in progesterone Progesterone capsules are used in combination with estrogen-containing medications in a postmenopausal woman with a uterus (womb).

Prometrium is a brand name for progesterone, a female hormone used to treat menstrual irregularities and prevent endometrial hyperplasia in postmenopausal women with a uterus.

  • Key uses: treatment of secondary amenorrhea and protection of the endometrium (lining of the uterus) in combination with estrogen-containing medications. 2

From the Research

Definition of Prometrium

  • Prometrium is a brand name for the medication progesterone, which is a hormone replacement therapy used in postmenopausal women 3, 4, 5, 6, 7.

Uses of Prometrium

  • Prometrium is used to prevent endometrial hyperplasia (a condition where the lining of the uterus grows too thick) in women who are taking estrogen replacement therapy 3, 4, 5, 6, 7.
  • It is also used to treat irregular bleeding and spotting in women who are taking estrogen replacement therapy 4, 5, 7.

Mechanism of Action

  • Prometrium works by reducing the risk of endometrial hyperplasia and carcinoma (cancer of the uterus) in women who are taking estrogen replacement therapy 3, 4, 5, 6, 7.
  • It does this by balancing the effects of estrogen on the uterus, which can help to prevent the growth of abnormal cells 6, 7.

Dosage and Administration

  • The dosage and administration of Prometrium can vary depending on the specific condition being treated and the individual woman's needs 3, 4, 5, 6, 7.
  • It is typically taken orally, and the dosage can range from 100-200 mg per day 6, 7.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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