Progesterone 100 mg Capsules: What They Treat and How to Take Them
A single 100 mg micronized progesterone capsule taken at bedtime is the standard way to protect your uterus when you use daily estrogen therapy for menopause symptoms.
The 100 mg micronized progesterone capsule is an FDA-approved oral hormone that keeps the uterine lining from over-growing when you use continuous estrogen therapy. You swallow it once every night with a snack, then let your body convert the capsule’s natural progesterone into the calming hormone levels your uterus needs. Because the product is suspended in peanut oil, anyone with a peanut allergy needs a different form, and you should never change the dose without a doctor’s direction.
- A 100 mg dose of oral micronized progesterone is enough to counteract the endometrial-stimulating effect of 1 mg oral estradiol in most post-menopausal women (Lobo et al., 2019).
- The capsule should be taken once daily at bedtime, with food, because progesterone can cause dizziness and because fat improves absorption (DailyMed).
- The softgel contains peanut oil, so people with peanut allergy need an alternative such as an intravaginal product or a peanut-free compounded capsule (DailyMed).
- Sleepiness, headache, and breast tenderness are the most reported side effects in the REPLENISH trial of the combined estradiol/progesterone capsule (Lobo et al., 2019).
- Rx.com can prescribe and ship progesterone 100 mg capsules after a quick online visit with a licensed U.S. provider; no insurance or long-term contract required.
What a 100 mg progesterone capsule is
Progesterone 100 mg capsules are softgel pills filled with micronized (very finely ground) natural progesterone dissolved in peanut oil. The micronization allows your intestines to absorb the hormone efficiently, and the oil vehicle slows breakdown so you get a smooth blood-level curve overnight (DailyMed). The FDA approved the branded version (Prometrium) for:
- Protecting the endometrium in post-menopausal women taking daily estrogens.
- Secondary amenorrhea (absence of periods in premenopausal women).
Generic micronized progesterone 100 mg is therapeutically equivalent. You will often see it prescribed alongside systemic estrogen such as an estradiol pill, patch, or gel. For more background on systemic estrogen options, read our guide how to get an estradiol patch prescription online.
| Oral progesterone strengths | Typical HRT schedule | Main clinical use |
|---|---|---|
| 100 mg capsule | Every night, continuous | Endometrial protection in estrogen therapy |
| 200 mg capsule | Every night for the last 12 days of each 28-day cycle | Cyclic HRT regimen |
| 300 mg total (3×100 mg) | Bedtime dose in infertility protocols | Luteal phase support (Khrouf et al., 2016) |
How the 100 mg dose protects your uterus
Estrogen stimulates the uterine lining, while progesterone keeps that growth in check. In the REPLENISH phase 3 trial, adding 100 mg of micronized progesterone to 1 mg of estradiol kept the rate of endometrial hyperplasia below 1 percent over 12 months, which met the FDA’s safety benchmark (Lobo et al., 2019). The mean steady-state progesterone level with this dose was 0.55 ng/mL, enough to transform the endometrium into its stable secretory phase.
Natural metabolism: After you swallow the capsule, your liver converts part of the hormone into allopregnanolone, a neurosteroid that binds to GABA-A receptors and explains why many women feel sleepy within an hour. This is why bedtime dosing is recommended.
How to take the capsule safely
Bedtime with a snack: Take one 100 mg capsule with a small amount of food-such as yogurt or a cracker-right before bed. Food increases bioavailability by about 10 percent, and taking it at night limits next-day drowsiness (DailyMed).
Swallow whole, do not chew: The softgel must stay intact so the micronized progesterone reaches the small intestine. If you have trouble swallowing pills, ask your provider about a peanut-free compounded suspension.
No alcohol right after the dose: Both alcohol and progesterone potentiate GABA signaling and can deepen sedation.
For a step-by-step of what happens during a digital menopause visit, see what to expect from an online menopause visit.
Is a 100 mg capsule right for tonight?
Check the column that fits your situation:
✅ Safe to take as prescribed
- You took your systemic estrogen earlier today
- No peanut or soy allergy
- Not pregnant or breastfeeding
- No severe liver disease
- Able to go to bed within 30 minutes of the dose
🏥 Wait and talk to your provider
- History of peanut anaphylaxis
- Unexplained vaginal bleeding
- Active blood clot or clotting disorder
- Current hormone-sensitive cancer
- Severe dizziness or grogginess after prior doses
| Side effect in REPLENISH (E2 1 mg / P4 100 mg) | Incidence over 12 months |
|---|---|
| Somnolence (sleepiness) | 5.4 % |
| Headache | 3.8 % |
| Breast tenderness | 2.9 % |
| Dizziness | 1.7 % |
| Nausea | 1.5 % |
Ready for convenient nightly protection?
Start an online visit and get progesterone 100 mg capsules shipped to your door if prescribed.
Who should and should not use it
Most post-menopausal women with a uterus who take daily estrogen benefit from the 100 mg capsule. However, the product carries the same boxed warning that applies to all estrogen-progestogen therapy: an elevated risk of stroke, blood clots, heart attack, and breast cancer in certain settings (DailyMed). Age under 60 years and treatment starting within 10 years of menopause appear to have a more favorable risk-benefit ratio, but personal history matters.
Peanut allergy caveat: Prometrium and most generic progesterone capsules contain peanut oil, so they are not for people with a peanut allergy. Tell your provider about any allergies so they can consider other options.
Common side effects and fixes
Sleepiness: This is the intended effect of the dose; keep liquids at the bedside in case you wake up thirsty.
Mild dizziness: Sit on the edge of the bed for a few seconds before standing. If dizziness lasts into the next day, tell your provider.
Breast tenderness: Usually improves after two to three cycles. Wearing a supportive bra and limiting caffeine can help.
Spotting or bleeding: Light spotting in the first three months is common as the uterine lining stabilizes. Persistent bleeding needs evaluation; see our article on spotting after HRT.
Mood changes: Rare, but let your provider know if anxiety or low mood worsens so they can assess whether a dose timing adjustment or different route is appropriate.
Cost and how to get a prescription online
Cash prices at local pharmacies: Generic progesterone 100 mg is often inexpensive, but prices vary by pharmacy and zip code. If you already have a prescription, compare progesterone coupon prices before you fill.
Direct-to-doorway care: Skip the pharmacy trip by completing a brief menopause intake. A licensed U.S. provider reviews your history and, if appropriate, prescribes progesterone from Rx.com. If a prescription is granted, it ships free to your door.
Remember estrogen: Systemic estrogen is the other half of therapy. If you and your provider decide on estradiol, see estrogen therapy from Rx.com.
For a deep dive into shipping logistics, read how HRT is delivered to your door.
🚨 When to Contact Your Healthcare Provider
Contact your doctor immediately if you experience any of the following:
- Sudden chest pain or shortness of breath: could be a blood clot in the lungs
- One-sided leg swelling with warmth: sign of a deep vein thrombosis
- New severe headache or vision changes: possible stroke warning
- Yellowing of the skin or eyes: could indicate liver injury
- Persistent or heavy vaginal bleeding: may signal endometrial changes
- Lump in the breast: needs prompt imaging
- Severe dizziness that does not improve: may require dose or route adjustment
- Signs of an allergic reaction such as hives, lip swelling, or trouble breathing
Scientific References
- Lobo RA, Liu J, Stanczyk FZ, et al. Estradiol and progesterone bioavailability for moderate to severe vasomotor symptom treatment and endometrial protection with the continuous-combined regimen of TX-001HR (oral estradiol and progesterone capsules). Menopause. 2019.
- Khrouf M, Slimani S, Khrouf MR, et al. Progesterone for Luteal Phase Support in In Vitro Fertilization: Comparison of Vaginal and Rectal Pessaries to Vaginal Capsules: A Randomized Controlled Study. Clin Med Insights Womens Health. 2016.
- DailyMed. dailymed.nlm.nih.gov.
Frequently Asked Questions
Can I cut or open a progesterone 100 mg capsule?
No. Cutting or opening the softgel spills the hormone and changes absorption. Swallow it whole or ask your provider for a different formulation if swallowing is difficult.
Is 100 mg enough if I use an estradiol patch instead of a pill?
Yes for most doses up to 0.05 mg/day, according to expert consensus, but your provider may check a pelvic ultrasound if bleeding occurs to confirm the lining is thin.
What if I forget my bedtime dose?
If you remember the next morning, skip it and take your regular dose that night. Do not double up unless your prescriber gives specific instructions.
Does progesterone 100 mg cause weight gain?
Clinical trials have not shown significant weight changes compared with placebo at this dose, but fluid retention can make weight fluctuate slightly.
Can I drink wine after taking the capsule?
It is best to avoid alcohol within two hours of the dose because both substances are sedating and may increase fall risk.
Is the capsule vegetarian?
No. The gelatin shell is animal derived and the fill oil is peanut based. A compounded plant-derived capsule may be available from a specialty pharmacy.
Will progesterone help with sleep on its own?
Many women report better sleep because progesterone’s metabolite allopregnanolone has calming effects, but the FDA approves the capsule only for hormone therapy, not as a sleep aid.
Can men use progesterone 100 mg capsules?
Progesterone is not FDA-approved for use in men and may cause unwanted side effects such as lowered testosterone and mood changes.
Start nightly progesterone protection now
Answer a few health questions and a licensed provider will decide whether progesterone 100 mg capsules are right for you. If prescribed, your medication ships to your home.
