What Is Estradiol/Norgestimate (Prefest)? Uses, Dosage, and What You Need to Know in 2026

If you've been prescribed Prefest or are exploring hormone replacement therapy options for menopause management, this guide gives you the essential facts about Estradiol/Norgestimate — what it is, what it treats, how it works, how to take it correctly, and what to watch for. All the information you need in one place.

What Is Estradiol/Norgestimate (Prefest)?

Prefest is the brand name for a prescription combination hormone therapy medication containing estradiol (an estrogen) and norgestimate (a progestin). It is manufactured by Teva Pharmaceuticals and is available only as a brand-name product — no generic equivalent exists as of 2026.

Prefest is classified as a menopausal hormone therapy (MHT) medication. It is specifically formulated for postmenopausal women who still have their uterus. The progestin component protects the uterine lining from the proliferative effects of estrogen alone, reducing the risk of endometrial cancer.

What Is Prefest Used For?

Prefest is FDA-approved for three indications in postmenopausal women with an intact uterus:

1. Vasomotor symptoms (hot flashes, night sweats): Treatment of moderate to severe hot flashes and night sweats associated with menopause. Hot flashes are one of the most disruptive menopausal symptoms, and estrogen replacement therapy is the most effective treatment available.
2. Vulvovaginal atrophy symptoms: Treatment of moderate to severe symptoms of vaginal and vulvar atrophy — including vaginal dryness, itching, pain during sex, and recurrent urinary symptoms. (Note: If vaginal symptoms are the only indication, topical vaginal products may be preferred.)
3. Postmenopausal osteoporosis prevention: Prevention of bone loss (osteoporosis) in postmenopausal women. Estrogen helps maintain bone density, and Prefest is one of many HRT options approved for this use. (Note: If osteoporosis prevention is the only goal, non-estrogen medications should be considered first.)

How to Take Prefest: The Dosage Regimen

Prefest has a unique alternating regimen that differs from most other oral HRT tablets. This is important to understand before you start:

• Days 1–3: Take one pink tablet (1 mg estradiol only) each day.
• Days 4–6: Take one white tablet (1 mg estradiol + 0.09 mg norgestimate) each day.
• Repeat this 6-day cycle continuously without interruption.
• Each blister card contains 30 tablets (15 pink + 15 white) arranged in the correct order.
• Always follow the blister card sequence — do not take tablets out of order.

This approach is called CIOP — constant estrogen/intermittent progestogen. The estrogen is continuous (providing consistent symptom relief), while the progestin is given only every other 3 days (reducing total progestin exposure compared to daily combined regimens).

Practical Tips for Taking Prefest

• Take your tablet at the same time every day for best results.
• Prefest can be taken with or without food. If nausea occurs, try taking it with a meal.
• If you miss a dose, take it as soon as you remember — unless it's almost time for your next dose. Do not double up.
• If you miss 2 doses in a row, take the next tablet in order and continue. Call your doctor if you miss more than 2 doses.
• Always start a new blister card on the day after finishing the previous one. Do not take breaks between packs.
• Store at room temperature (68–77°F / 20–25°C), away from moisture and heat.

Who Should NOT Take Prefest?

Prefest is contraindicated in women with:

• Known or suspected breast cancer or personal history of breast cancer
• Undiagnosed vaginal bleeding
• Active or history of blood clots (DVT, PE, stroke, or MI)
• Liver disease or dysfunction
• Pregnancy
• Prior hysterectomy (estrogen-only products are more appropriate for these patients)

How Long Does It Take for Prefest to Work?

Many patients notice some improvement in hot flashes and sleep within the first few weeks of starting Prefest. Full therapeutic effect typically develops within 1–3 months. If you don't notice significant improvement after 3 months, discuss your response with your prescriber — a dose adjustment or change in HRT formulation may be warranted.

The Bottom Line

Estradiol/Norgestimate (Prefest) is an effective FDA-approved HRT for postmenopausal women with an intact uterus seeking relief from hot flashes, vaginal symptoms, and osteoporosis prevention. Its unique alternating cycle regimen requires following the blister card order carefully. For a deeper explanation of how Prefest works in the body, see our guide on how Estradiol/Norgestimate works.