Micronized Progesterone
Pronunciation: (my-KROH-nized proh-JES-ter-own).
- Generic name
- Micronized progesterone
- Brand names
- Naturogest, Utrogestan, Progestan, Susten, Gestone, First-Progesterone
- Drug class
- Progestin hormone
Availability and supply rules vary by country
Trade names by country: India
Australia: · Full directory
What Micronized progesterone is and how it works
Uses, formulations, monitoring, and supply rules can differ by patient, product, and country. Follow the exact local product information and professional advice.
Mechanism of action: how Micronized progesterone works
Micronized progesterone acts as a bioidentical progestin, binding to progesterone receptors in target tissues. It transforms the endometrium from a proliferative to a secretory state, opposes estrogen-induced endometrial hyperplasia, and supports early pregnancy by preparing the endometrium for implantation and maintaining gestation. (1)
What Micronized progesterone is used for
Hormone replacement therapy (HRT), combined with estrogen, in postmenopausal women with an intact uterus
Oral capsule formulation (e.g. Utrogestan 100mg, US Prometrium). (2) (3)
Secondary amenorrhea (missed periods)
Luteal-phase support during fertility treatment (Assisted Reproductive Technology / IVF)
Vaginal formulation; a distinct product/route from the oral HRT capsule. (2) (3)
Support of early pregnancy in some cases of infertility or recurrent miscarriage
Specialist-supervised use; distinct from, and not the same product/indication as, the oral HRT capsule. (2) (3)
Before taking Micronized progesterone
Do not take / not appropriate for
- active or history of thromboembolic disorders, severe liver dysfunction, known or suspected malignancy of breast or genital organs, undiagnosed vaginal bleeding, and hypersensitivity to progesterone. (Contraindication) (2)
Tell your clinician about
(2) (3)How to take Micronized progesterone
- General Instructions: Take micronized progesterone exactly as prescribed by your healthcare provider. It is usually taken once daily at bedtime to reduce drowsiness during the day.. Adult Dosing: Typical adult dose for hormone replacement therapy is 100–200 mg orally at bedtime for 12–14 days per month, or as directed. For luteal support in fertility treatments, dosing and route (oral/vaginal) may vary.. Pediatric Dosing: Safety and efficacy in children have not been established. Use only under specialist supervision.. Administration: Swallow capsules whole with water. For vaginal use, insert the capsule as directed. Do not crush or chew.. When To Stop: Do not stop taking this medication abruptly without consulting your healthcare provider. If you develop a new contraindication (such as a blood clot, suspected pregnancy while on the HRT capsule, or a serious side effect), contact your healthcare provider promptly so they can advise on whether to continue or stop treatment.. Storage: Store at room temperature, away from moisture and heat. Keep out of reach of children.
- This page does not provide a dose calculator. Dosing must follow the prescriber, pharmacist, or product label.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (2) (3)
Missed dose
If you miss a dose, take it as soon as you remember unless it is almost time for your next dose. Do not double up doses. If you are unsure, consult your healthcare provider.
Overdose
In case of overdose, seek emergency medical attention. Symptoms may include nausea, vomiting, drowsiness, or dizziness. Supportive care is the mainstay of treatment. (2) (3)
Side effects
Side effects and their urgency vary; report severe, persistent, or concerning symptoms to a healthcare professional.
Drowsiness
Incidence: Reported in the clinician-authored database; frequency not established
Dizziness
Incidence: Reported in the clinician-authored database; frequency not established
Headache
Incidence: Reported in the clinician-authored database; frequency not established
Breast tenderness
Incidence: Reported in the clinician-authored database; frequency not established
Bloating
Incidence: Reported in the clinician-authored database; frequency not established
Mild nausea
Incidence: Reported in the clinician-authored database; frequency not established
Unusual vaginal bleeding, severe headache, vision changes, chest pain, leg swelling/pain, or other signs of a possible blood clot or stroke — seek prompt medical attention.
(1)Signs of an allergic reaction (e.g. to peanut oil or soya) such as swelling, hives, or difficulty breathing — seek emergency care immediately.
(2)Serious warnings
FDA BOXED WARNING (US oral capsule product) / prominent SmPC warning (UK) — serious
Symptoms: FDA BOXED WARNING (US oral capsule product) / prominent SmPC warning (UK): estrogen-plus-progestin therapy is not for preventing cardiovascular disease and carries an increased risk of heart attack, stroke, blood clots (deep vein thrombosis and pulmonary embolism), and invasive breast cancer. Quantified risk from UK labeling: combined HRT carries roughly 1.3-3 times the usual risk of a blood clot (highest in the first year of use), up to about 1.5 times the usual risk of ischaemic stroke, and roughly 1.7 times the usual risk of breast cancer after 5 or more years of combined use. Report any signs of a blood clot, stroke, or heart problem to your care team immediately.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (3)
PEANUT AND SOYA ALLERGY WARNING — serious
Symptoms: PEANUT AND SOYA ALLERGY WARNING: capsule formulations of this medicine (Utrogestan and Prometrium) are made using peanut (arachis) oil and contain soya lecithin. They must never be used by anyone with a peanut allergy. Because of possible cross-reactivity between soya and peanut allergy, people with a soya allergy should also discuss this with their prescriber before use. This is a genuine contraindication, not a general precaution.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (3)
May cause drowsiness — serious
Symptoms: May cause drowsiness; take at bedtime. Not for use in pregnancy unless specifically prescribed for luteal support under specialist fertility care — this is a different clinical context from oral HRT use, where treatment should be discontinued immediately if pregnancy occurs. Monitor for signs of depression or mood changes. Report any unexplained vaginal bleeding immediately.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (3)
Contraindications recorded in the clinician database — serious
Symptoms: Contraindications recorded in the clinician database: Contraindications include active or history of thromboembolic disorders, severe liver dysfunction, known or suspected malignancy of breast or genital organs, undiagnosed vaginal bleeding, and hypersensitivity to progesterone or peanut oil. Use with caution in patients with cardiovascular disease, renal or hepatic impairment, diabetes, migraine, or depression.
Action: Follow the urgency stated and seek prompt or emergency care when indicated. (2) (3)
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Recorded interactions | Micronized progesterone may interact with certain medications, including some anticonvulsants (e.g., phenytoin, carbamazepine), rifampin, and herbal supplements like St. John's wort, which can reduce its effectiveness. It may also interact with other hormone therapies. Always inform your healthcare provider of all medications and supplements you are taking. | (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Pregnancy
Use in pregnancy depends entirely on which formulation and indication applies. For the oral HRT-indicated capsule, treatment should be discontinued immediately if pregnancy occurs — this product is not intended for use during pregnancy. Separately, vaginal micronized progesterone is deliberately used, under specialist fertility-care supervision, to support the luteal phase and early pregnancy in some cases of infertility or recurrent miscarriage. These are different clinical uses of related products — always follow the specific guidance from the clinician managing your care. (2) (3)
Breastfeeding
For the oral HRT-indicated capsule formulation, UK labeling states this medicine is contraindicated during breastfeeding because detectable amounts of progesterone pass into breast milk. Discuss any other formulation or use with your healthcare provider before breastfeeding. (2) (3)
Children
Frequency: Not applicable. Weight Based: Not recommended for pediatric use. Max Daily Dose: Not applicable. Max Single Dose: Not applicable. Age Restrictions: Safety not established in children (2) (3)
Renal_impairment
Per the FDA Prometrium label and UK MHRA Utrogestan SmPC reviewed for this page, no formal pharmacokinetic studies of renal or hepatic disease on progesterone disposition have been conducted. Because progesterone is hepatically metabolized, both labels advise it is CONTRAINDICATED in severe hepatic impairment/disease, with careful monitoring needed in mild-to-moderate hepatic impairment. Because progesterone metabolites are eliminated mainly by the kidneys, both labels advise use with caution and careful monitoring in renal dysfunction, without a specific reduced-dose figure. (2) (3)
Hepatic_impairment
Per the FDA Prometrium label and UK MHRA Utrogestan SmPC reviewed for this page, no formal pharmacokinetic studies of renal or hepatic disease on progesterone disposition have been conducted. Because progesterone is hepatically metabolized, both labels advise it is CONTRAINDICATED in severe hepatic impairment/disease, with careful monitoring needed in mild-to-moderate hepatic impairment. Because progesterone metabolites are eliminated mainly by the kidneys, both labels advise use with caution and careful monitoring in renal dysfunction, without a specific reduced-dose figure. (2) (3)
Monitoring
(2) (3)Storage
Per UK labeling for Utrogestan: no special storage precautions are required (shelf life approximately 3 years). The clinician-authored record additionally advises keeping at room temperature away from moisture and heat, and out of reach of children — consistent with standard room-temperature storage.
Professional information
Clinician-facing context only. This section does not replace current product labeling.
United Kingdom (Utrogestan 100mg oral capsule SmPC)
Indication: Hormone replacement therapy (with estrogen)
Dose summary: 200 mg daily at bedtime for 12 days during the latter half of each cycle (days 15-26), or 100 mg at bedtime on days 1-25 of each cycle. Should not be taken with food.
Renal context: Neither the FDA Prometrium label nor the UK MHRA Utrogestan SmPC gives a specific renal-impairment dose reduction; both advise using progesterone with caution and careful monitoring in patients with renal dysfunction, since progesterone metabolites are eliminated mainly by the kidneys. (2)
General (fertility care)
Indication: Luteal-phase support
Dose summary: 200 mg to 400 mg orally once daily at bedtime, or a vaginal formulation as directed by the fertility specialist — exact dose and route depend on the specific product and treatment protocol.
Renal context: Neither the FDA Prometrium label nor the UK MHRA Utrogestan SmPC gives a specific renal-impairment dose reduction; both advise using progesterone with caution and careful monitoring in patients with renal dysfunction, since progesterone metabolites are eliminated mainly by the kidneys. (1)
Frequently asked questions
What is micronized progesterone (Utrogestan) used for?
It is used for hormone replacement therapy in menopause, to support pregnancy in women with infertility or recurrent miscarriage, and to treat menstrual disorders such as irregular periods or amenorrhea.
How should I take micronized progesterone?
Take it exactly as prescribed, usually at bedtime. It may be taken orally or inserted vaginally, depending on your condition.
What are the most common side effects?
Common side effects include drowsiness, dizziness, headache, breast tenderness, bloating, and mild nausea.
Can I use micronized progesterone during pregnancy?
It may be prescribed for luteal support in early pregnancy, but should not be used during pregnancy unless specifically directed by your doctor.
What should I do if I miss a dose?
Take the missed dose as soon as you remember, unless it is almost time for your next dose. Do not double up doses.
Are there any foods or drugs I should avoid?
Avoid alcohol and other sedating medications. Inform your doctor about all other drugs and supplements you are taking.
When should I contact my doctor while taking this medication?
Contact your doctor if you experience unusual vaginal bleeding, severe headache, vision changes, chest pain, or signs of a blood clot.
What happens if I take too much Micronized progesterone (Utrogestan)?
Taking too much Micronized progesterone (Utrogestan) can lead to symptoms such as severe drowsiness, dizziness, nausea, vomiting, or vaginal bleeding. If you suspect an overdose, it is crucial to seek immediate medical attention or contact emergency services. Do not attempt to self-treat an overdose.
Can I drink alcohol while taking Micronized progesterone (Utrogestan)?
It is generally advisable to limit or avoid alcohol consumption while taking Micronized progesterone (Utrogestan). Alcohol can exacerbate some of the common side effects of progestin hormones, such as drowsiness and dizziness, potentially impairing your ability to drive or operate machinery. Discuss alcohol use with your healthcare provider.
Is Micronized progesterone (Utrogestan) safe during pregnancy?
Micronized progesterone (Utrogestan) is used in certain situations during pregnancy, particularly for luteal phase support in fertility treatments and for the prevention of preterm birth. However, its safety and appropriate use during pregnancy are highly dependent on individual circumstances. Always consult your doctor to determine if it is safe and appropriate for your specific pregnancy needs.
What is the mechanism of action of Micronized progesterone?
Micronized progesterone acts as a bioidentical progestin, binding to progesterone receptors in target tissues. It transforms the endometrium from a proliferative to a secretory state, opposes estrogen-induced endometrial hyperplasia, and supports early pregnancy by preparing the endometrium for implantation and maintaining gestation. (1)
What is the generic name of Micronized Progesterone?
The generic name is Micronized progesterone. It is sold under brand names including Naturogest, Utrogestan, Progestan, Susten, Gestone, First-Progesterone.
What class of drug is Micronized progesterone?
Micronized Progesterone is classed as: Progestin hormone.
References
- Micronized progesterone (Utrogestan) — clinician-authored recordMedGuideGlobal internal clinician-authored medicine record · Global · accessed 2026-08-06 · source 1
- Utrogestan 100 mg capsules — Summary of Product CharacteristicsMedicines and Healthcare products Regulatory Agency (UK) via electronic Medicines Compendium · United Kingdom · accessed 2026-08-06 · source 2
- PROMETRIUM (progesterone, USP) capsules for oral use — prescribing informationU.S. Food and Drug Administration via DailyMed · United States · accessed 2026-08-06 · source 3
- PROGESTERONE MICRONIZED POWDER [CHEMO BIOSYNTHESIS SRL] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 4
- Micronized progesterone — RxNorm normalized drug concept (RXCUI 259409)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 5
Brand names by country
Single-ingredient Micronized progesterone names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
India
- Susten200 mg, 300 mg, 400 mg, 8% w/w gel · Sun Pharmaceutical Industries Ltd
- Endogest100 mg, 300 mg SR, 400 mg SR · Cipla Ltd
- GestoFIT200 mg, 300 mg · Alembic Pharmaceuticals Ltd
- GEStone400 mg · Ferring Pharmaceuticals
- Progestone200 mg · Knoll Healthcare Pvt Ltd
- Gesterol200 mg · Neon Laboratories Ltd
- GestoFORD100 mg, 200 mg, 300 mg SR · Leeford Healthcare Ltd
- Gestoserv200 mg · Leeford Healthcare Ltd
- EMPRogest8% w/w · Emcure Pharmaceuticals Ltd