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Progesterone

Brand names: Prometrium, Crinone, Endometrin

Progesterone is a natural hormone used with estrogen after menopause, to restart missed periods, and to support early pregnancy in fertility treatment.

Brand namesPrometrium, Crinone, Endometrin
Type of medicineProgesterone hormone
Prescription?Prescription
ImportantThis page is general information, not a prescription. Don't start, stop, or change a medicine without talking to your provider or pharmacist.

Overview

Capsules are often taken at bedtime because they can cause sleepiness.

What it's used for

  • Protecting the uterus during estrogen therapy
  • Missed periods (amenorrhea)
  • Fertility treatment and preventing preterm birth (some forms)

How to take it

  • Take capsules at bedtime.
  • Vaginal forms are used as directed.

Your dose depends on your health and other medicines. Always follow your prescription label, and ask your pharmacist if anything is unclear.

Side effects

Common side effects

  • Sleepiness or dizziness
  • Breast tenderness
  • Headache
  • Bloating
  • Mood changes
Call 911Chest pain, sudden shortness of breath, or signs of a stroke
Call your provider todayPain or swelling in one leg
Call your provider todayUnusual vaginal bleeding

Warnings

  • Boxed warnings (with estrogen): higher risk of heart disease, stroke, clots, breast cancer, and dementia in some older women.
  • Capsules contain peanut oil.

Other medicines, foods, and alcohol

  • Some seizure medicines and rifampin lower its effect.
  • Alcohol and sedating medicines add to drowsiness.

Tell your provider and pharmacist about every medicine, vitamin, and supplement you take.

Pregnancy and breastfeeding

Some forms are used to support pregnancy. Use only as your provider directs.

Missed doses, overdose, and storage

If you miss a dose

Take it as soon as you remember, unless it's almost time for your next dose. Then skip the missed dose. Don't take two doses at once.

If someone takes too much

Call Poison Control at 1-800-222-1222 or get help online at poison.org. Call 911 if the person collapses, has a seizure, has trouble breathing, or can't be woken.

Storing it

Store at room temperature, away from heat and moisture (not in the bathroom), and out of reach of children and pets.

Conditions it's used for

Sources

Last updated 2026-11-13.