What is progesterone, and how does it work (mechanism of action)?

Progesterone is a man-made medication derived from a plant source and is identical to the female hormone, progesterone produced in the ovaries. It promotes the development of the mammary glands, causes changes in the endometrium, which lines the uterus, relaxes uterine smooth muscles, blocks ovulation within the ovaries, and maintains pregnancy. Progesterone was approved in May, 1998.

What brand names are available for progesterone?


Is progesterone available as a generic drug?


Do I need a prescription for progesterone?


What are the side effects of progesterone?

Side effects of progesterone are headache, dizziness, fatigue, abdominal pain, nausea, breast tenderness, joint pain, depression, mood swings, and hot flashes.

Progesterone also isassociated with cardiovascular disorders, breast cancer, and possibly dementia in postmenopausal women.

What is the dosage for progesterone?

Prevention of Endometrial Hyperplasia: 200 mg by mouth once daily at bedtime for 12 consecutive days per 28 day cycle. Treatment of Secondary Amenorrhea: 400 mg by mouth once daily at bedtime for 10 days.


The vagina includes the labia, clitoris, and uterus. See Answer

Which drugs or supplements interact with progesterone?

Progesterone should be used with caution with ketoconazole (Nizoral), clarithromycin (Biaxin), and erythromycin (Ery-Tab) because they slow the breakdown of progesterone and increase its levels in the body.

Is progesterone safe to take if I'm pregnant or breastfeeding?

Progesterone should not be used during pregnancy.

Progesterone may be found in trace amounts in breast milk in women taking progesterone capsules.

What else should I know about progesterone?

What preparations of progesterone are available?

Capsules: 100 and 200 mg

How should I keep progesterone-oral stored?

Progesterone capsules should be stored between 20 C to 25 C (68 F to 77 F) and should be protected from excessive moisture.


Progesterone (Prometrium) is a synthetically produced hormone used to help regulate the uterine lining in post-menopausal women. Side effects, drug interactions, dosage, storage, and pregnancy safety information should be reviewed prior to taking this medication.

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Medically reviewed by John P. Cunha, DO, FACOEP; Board Certified Emergency Medicine


FDA Prescribing Information
Progesterone – Medscape