Overview
Progesterone is a natural progestin hormone used primarily in hormone replacement therapy to prevent endometrial hyperplasia in postmenopausal women receiving estrogen. It is also indicated for the treatment of secondary amenorrhea. The medication works by transforming proliferative endometrium into secretory endometrium.
Mechanism of Action
Progesterone is a natural progestin that binds to progesterone receptors in the uterus, ovaries, and other tissues. It transforms proliferative endometrium into secretory endometrium, inhibits gonadotropin secretion, and prevents endometrial hyperplasia in estrogen-treated women.
Indications
- Prevention of endometrial hyperplasia in nonhysterectomized postmenopausal women receiving conjugated estrogens
- Treatment of secondary amenorrhea
Common Doses
- 100 mg
- 200 mg
Dosage
For endometrial hyperplasia prevention: 200 mg orally daily for 12 days per 28-day cycle with conjugated estrogens. For secondary amenorrhea: 400 mg orally daily for 10 days. Administer at bedtime to minimize dizziness and drowsiness.
Contraindications
- Hypersensitivity to progesterone or any capsule ingredients (contains peanut oil)
- Abnormal genital bleeding of unknown etiology
- Known, suspected, or history of breast cancer
- Active deep vein thrombosis, pulmonary embolism or history of these conditions
- Active arterial thromboembolic disease or history of stroke/MI
- Known liver dysfunction or disease
Side Effects
- Headache
- Breast tenderness
- Joint pain
- Depression
- Dizziness
- Abdominal bloating
- Hot flashes
- Urinary problems
- Abdominal pain
- Vaginal discharge
- Nausea/vomiting
- Chest pain
- Diarrhea
- Night sweats
- Breast pain
- Swelling of hands and feet
- Vaginal dryness
- Constipation
Interactions
- May decrease effectiveness of anticoagulants
- May interact with CYP450 enzyme inducers (rifampin, carbamazepine, phenytoin)
- May increase effects of CNS depressants
- May alter glucose metabolism affecting diabetes medications
Counseling Points
- Take at bedtime to minimize dizziness and drowsiness
- Report any signs of allergic reaction immediately (especially if allergic to peanuts)
- Do not use during pregnancy
- Use effective contraception if sexually active
- Report unusual vaginal bleeding, chest pain, shortness of breath, or severe headaches
- Avoid alcohol and other CNS depressants
- May cause dizziness - avoid driving or operating machinery until effects are known