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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Limited Use [what does this mean?]
Generic drug name: progesterone (proe JES ter one)
Brand name(s): PROMETRIUM
GENERIC: not available FAMILY: Progestins
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

The progestins have caused genital abnormalities in both male and female infants born to mothers taking these drugs during pregnancy. Because of the potential for serious adverse effects to the fetus, these drugs should not be used by pregnant women.

Breast-feeding Warning

Progestins are excreted in human milk. Because of the potential for adverse effects in nursing infants, you should not take these drugs while nursing.

Safety Warnings For This Drug [top]

FDA Black Box Warning

WARNING: CARDIOVASCULAR DISORDERS, BREAST CANCER and PROBABLE DEMENTIA FOR ESTROGEN PLUS PROGESTIN THERAPY

Cardiovascular Disorders and Probable Dementia

Estrogens plus progestin therapy should not be used for the prevention of cardiovascular disease or dementia. The Women’s Health Initiative (WHI) estrogen plus progestin substudy reported increased risks of deep vein thrombosis (clots in the large veins, typically in the legs), pulmonary embolism (clots in the lungs), stroke and heart attack in postmenopausal women (50 to 79 years of age) during 5.6 years of treatment with daily oral conjugated estrogens (0.625 mg) combined with medroxyprogesterone acetate (MPA) (2.5 mg), relative to placebo.

The WHI Memory Study (WHIMS) estrogen plus progestin substudy of the WHI reported an increased risk of developing probable dementia in postmenopausal women 65 years of age or older during four years of treatment with daily conjugated estrogen (0.625 mg) combined with MPA (2.5 mg), relative to placebo. It is unknown whether this finding applies to younger postmenopausal women.

Breast Cancer

The WHI estrogen plus progestin substudy also demonstrated an increased risk of invasive breast cancer. In the absence of comparable data, these risks should be assumed to be similar for other doses of conjugated estrogen and MPA, and other combinations and dosage forms of estrogens and progestins. Progestins with estrogens should be prescribed at the lowest effective dose and for the shortest duration consistent with treatment goals and risks for the individual woman.

Beware of Compounding Pharmacists

Progesterone capsules are promoted by compounding pharmacists for various uses.

Drugs compounded by pharmacists are not FDA-approved. They have not been shown to be safe or effective for use and are produced in facilities that do not have to meet good manufacturing practice guidelines.

Prometrium capsules contain peanut oil and should never be used by patients allergic to peanuts.

Facts About This Drug [top]

This drug is approved by the FDA to prevent endometrial hyperplasia (changes in the cells of the lining of the uterus that may be precancerous) in women who are taking conjugated estrogens and to treat women who have secondary amenorrhea (lack of menstruation for at least three months in women who had been menstruating in the absence of pregnancy or menopause).[1] It is available in oral capsules and an injectable form.

Progesterone should not be used in a number of situations. These...

This drug is approved by the FDA to prevent endometrial hyperplasia (changes in the cells of the lining of the uterus that may be precancerous) in women who are taking conjugated estrogens and to treat women who have secondary amenorrhea (lack of menstruation for at least three months in women who had been menstruating in the absence of pregnancy or menopause).[1] It is available in oral capsules and an injectable form.

Progesterone should not be used in a number of situations. These include during pregnancy; in women who have blood clots or a history of blood clots, severe liver problems, cancer of the breast or genital organs, undiagnosed vaginal bleeding or missed abortion; or as a diagnostic test for pregnancy.

Progesterone can mask onset of menopause. It may precipitate attacks of porphyria, a rare enzyme deficiency, which is particularly prevalent among Scandinavian women. Symptoms are pain in the abdomen, arms, back and legs and muscle weakness.

A common adverse effect is drowsiness, which may decline over time. It may cause edema (swelling of ankles and feet), which may be aggravated by epilepsy, migraine, asthma, or heart or kidney dysfunction.

There is no evidence that progesterone is effective for treating premenstrual syndrome.[2]

The injectable form of progesterone, which contains sesame oil, is associated with a severe type of lung disease called acute eosinophilic pneumonia.[3] Symptoms include fever and shortness of breath and generally develop within two to four weeks after starting the drug.

Before You Use This Drug [top]

Do not use if you have or have had:

  • abnormal and undiagnosed vaginal bleeding
  • undiagnosed urinary tract bleeding
  • breast cancer, known or suspected
  • inflammation of the veins
  • blood clots
  • pregnancy or are breast-feeding
  • allergy to progestins
  • allergy to peanuts
  • liver disease

Tell your doctor if you have or have had:

  • asthma
  • stroke
  • osteoporosis
  • epilepsy
  • high blood pressure
  • migraine headaches
  • kidney disease
  • liver disease
  • high cholesterol levels
  • mental depression or convulsions
  • diabetes
  • pulmonary embolism
  • disease of the heart or blood vessels

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Have regular checkups with your doctor.
  • Caution when driving or doing things requiring alertness, because progesterone may cause dizziness or drowsiness for one to four hours after dose.
  • Check with your doctor immediately if breakthrough bleeding continues for longer than three months or if your period is delayed by 45 days.
  • Check with your doctor immediately if you suspect you may be pregnant or a menstrual period is missed.
  • Check with your dentist if tenderness, swelling, or bleeding of gums occurs.
  • Tell your doctor you are taking this drug if you are scheduled for laboratory tests, as some may be affected by taking progestins.

How to Use This Drug [top]

  • Read the patient instructions.
  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

Evaluations of Drug Interactions 2003 lists no drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods as causing “highly clinically significant” or “clinically significant” interactions when used together with the drugs in this section. We also found no interactions in the drugs’ FDA-approved professional package inserts. However, as the number of new drugs approved for marketing increases and as more experience is gained with these drugs over time, new interactions may be discovered.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • stopping of menstrual periods
  • medium to heavy bleeding between regular monthly periods
  • spotting (light bleeding between regular monthly periods)
  • increased amount of menstrual bleeding at regular monthly periods
  • unexpected or increased flow of breast milk
  • mental depression
  • dry mouth
  • frequent urination
  • loss of appetite
  • unusual thirst
  • skin rash
  • headache or migraine
  • loss of or change in speech, coordination, or vision
  • pain or numbness in chest, arm, or leg
  • unexplained shortness of breath, sudden and severe

Call your doctor if these symptoms continue:

  • dizziness
  • drowsiness
  • bloating or swelling of ankles or feet
  • acne
  • breast pain or tenderness
  • hot flashes
  • trouble sleeping
  • loss of sexual desire
  • loss or gain of body, facial, or scalp hair
  • brown spots on exposed skin
  • nervousness
  • unusual tiredness or weakness
  • unusual or rapid weight gain
  • nausea

Periodic Tests[top]

Ask your doctor which of these tests should be done periodically while you are taking this drug:

  • breast exams
  • Pap test
  • physical exams

last reviewed April 30, 2021