What is Progesterone Micronized: Uses, Warnings & Interactions

Updated Apr 28, 2025  •  Published Dec 30, 2020

Progesterone micronized is a prescription female hormone used in menopausal hormone replacement therapy as well as a treatment for women who lose their period due to progestin deficiency. As a micronized oral drug, the progesterone in the capsule is divided into very tiny particles to increase absorption and bioavailability. Women take one daily dose, but the size of the dose will depend on the condition being treated.

Progesterone Micronized overview

BRAND NAMES:

  • Prometrium

Generic Names:

  • Progesterone micronized

Uses:

  • Helps prevent changes in the uterus in women who are taking estrogen after menopause. Also treats menstrual periods that have stopped before menopause.

Therapeutic Classes:

  • Progestin, endocrine-metabolic agent

Forms:

  • Capsule

How it’s taken:

  • By mouth

What is Progesterone Micronized used for?

Healthcare providers use progesterone micronized to prevent endometrial enlargement in women taking conjugated estrogens for menopausal symptoms. The FDA has also approved its use as a treatment for women who are not having periods (amenorrhea) because of progesterone deficiency.

What form(s) does Progesterone Micronized come in

  • Capsule

    • 100 mg

    • 200 mg

What are common Progesterone Micronized doses?

  • For the prevention of endometrial hyperplasia in women taking conjugated estrogens: 200 mg daily taken at bedtime for 12 days in a 28-day cycle

  • For the prevention of endometrial hyperplasia in women taking conjugated estrogens: 400 mg daily taken at bedtime for 10 days

Common Progesterone Micronized prescriptions

  • Progesterone Micronized
    100mg capsule

  • Progesterone Micronized
    200mg capsule

How to take Progesterone Micronized

  • Your doctor will tell you how much medicine to use. Do not use more than directed.

  • Please read the Patient Information sheet that comes with the capsules.

  • This medicine is usually taken every day for 10 to 12 days depending on the reason you are using it. 

  • If you also take estrogen, carefully follow the schedule for both medicines together.

  • Take the capsule at bedtime unless instructed otherwise.

  • Swallow the capsule whole with a glass of water.

  • If you have trouble swallowing this medicine, take it with a glass of water while standing up. Talk to the prescriber or a pharmacist if this does not help.

  • Store the medicine at room temperature protected from excessive moisture.

What to do if you miss a dose of Progesterone Micronized

  • Ask the prescriber what to do if a dose is missed. 

  • Do not double up a dose to make up for a missed dose.

Progesterone Micronized contraindications

  • This medicine is not right for everyone. Do not use it if you are pregnant or have:

    • Known allergies to progesterone or peanuts

    • Abnormal genital bleeding that has not been checked by a doctor

    • Active blood clot problems such as deep vein thrombosis or pulmonary embolism

    • A history of blood clot problems (including heart attack or stroke)

    • A history of breast cancer

    • Liver problems or a history of liver problems

Progesterone Micronized warnings

  • Tell any doctor or dentist who treats you that you are using this medicine. 

    • You may need to stop using this medicine several days before you have surgery or medical tests. 

    • You may also need to stop if you will be inactive for a long time. 

  • Tell the prescriber if you are pregnant, breastfeeding, or have:

    • Asthma

    • Epilepsy

    • Diabetes

    • Migraines

    • Endometriosis

    • Kidney problems

    • Heart problems

    • Liver problems

    • Thyroid problems

    • High calcium

    • Lupus

  • This medicine can cause serious problems including:

    • Blood clots leading to stroke, heart attack, vision loss, or similar conditions

    • Increased risk of breast cancer or endometrial cancer (for progestin and estrogen treatment)

    • Increased risk of dementia (in women older than 65 on both progesterone and estrogen treatment) 

    • Fluid retention

  • This medicine may make you dizzy or drowsy. Be cautious about driving or operating machinery.

Progesterone Micronized interactions

  • To avoid drug interactions, tell the prescribing healthcare provider about all the medications you take or plan to take before starting progesterone micronized.

  • Tell other healthcare professionals about taking progesterone micronized before they prescribe new medications.

Progesterone Micronized side effects

Serious side effects

Talk to a doctor if you notice any signs or symptoms of a possible serious side effect including:

  • Unusual vaginal bleeding

  • Breast lumps

  • Chest pain, trouble breathing, or coughing up blood

  • Depression

  • Rapid weight gain, swelling in your hands, ankles, or feet

  • Numbness or weakness on one side of your body, sudden or severe headache, changes in vision or speech, walking problems

  • Severe leg pain, severe chest pain, dizziness, faintness, vomiting

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing

Less serious side effects

  • Headache

  • Breast tenderness or pain

  • Joint pain

  • Depression

  • Dizziness

  • Bloating

  • Light breakthrough bleeding or spotting

  • Stomach or abdominal cramps

  • Urinary problems

  • Nausea

  • Vomiting

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