Short answer: Both are capsules with progesterone taken by mouth.12 Bijuva combines estradiol with 100 mg progesterone, one capsule each evening with food, for menopausal hot flashes in women with a uterus. Prometrium is progesterone alone: 200 mg at bedtime for 12 days of each 28-day cycle alongside conjugated estrogens to protect the uterine lining, or 400 mg for 10 days for secondary amenorrhea. Neither has a boxed warning.
| Bijuva | Prometrium | |
|---|---|---|
| What is in it | Estradiol 0.5 mg or 1 mg plus progesterone 100 mg1 | Progesterone 100 mg or 200 mg, in peanut oil2 |
| Approved for | Moderate to severe hot flashes from menopause in a woman with a uterus1 | Preventing endometrial hyperplasia in postmenopausal women on conjugated estrogens; secondary amenorrhea2 |
| Schedule | One capsule every evening with food; usually starting at 0.5 mg/100 mg1 | 200 mg at bedtime for 12 days in a row per 28-day cycle, or 400 mg at bedtime for 10 days2 |
| Uterine lining in label trials | Hyperplasia at 12 months: 0.33% on 0.5 mg/100 mg, 0.36% on 1 mg/100 mg, 0 on placebo1 | Hyperplasia over 36 months: 6% with conjugated estrogens plus Prometrium vs 64% on conjugated estrogens alone2 |
| Breast tenderness | 10.4% on 1 mg/100 mg and 4.0% on 0.5 mg/100 mg vs 0.7% on placebo1 | 27% with conjugated estrogens vs 6% on placebo2 |
| Missed dose | Take with food as soon as possible, unless within two hours of the next evening dose1 | No instruction in the label2 |
| Boxed warning | None in the current label1 | None2 |
Bijuva holds both hormones in one capsule taken daily, so no separate estrogen is added.1 Prometrium is used on its own for secondary amenorrhea, or on 12 days of each cycle by a woman who is also taking daily conjugated estrogens tablets.2 The Bijuva label says to consider starting it in women under 60 or within 10 years of menopause, and to try tapering or stopping every 3 to 6 months.1 The Prometrium label says it may cause short-lived dizziness and drowsiness, and its capsules contain peanut oil.2 These numbers come from separate trials with different people, lengths and methods, so they are not a head-to-head comparison.
Yes. Both labels draw on the WHI estrogen plus progestin trial for warnings on blood clots, stroke, heart attack and breast cancer, and both say treatment is stopped right away if one of these occurs or is suspected, and if feasible 4 to 6 weeks before surgery linked to clots.12 Bijuva also carries the estrogen warnings on gallbladder disease, vision problems and triglycerides.1
Which, if either, fits is for your prescriber. More detail: Bijuva side effects, Prometrium side effects, the Bijuva and Prometrium dosing schedules, the Bijuva missed-dose page, Prempro vs Activella: how do the two combined HRT tablets differ? and Prometrium vs Crinone: how do the oral and vaginal progesterone differ?.