Short answer: Both are once-weekly estradiol-only patches from Bayer.12 Menostar delivers 14 mcg a day and is approved only to prevent postmenopausal osteoporosis. Climara comes in six strengths from 0.025 to 0.1 mg a day and is also approved for hot flashes and vaginal atrophy. The Menostar label compares its blood levels with the lowest Climara patch. Both carry the estrogen boxed warning.
| Menostar | Climara | |
|---|---|---|
| Dose | 14 mcg estradiol per day, one strength1 | 0.025, 0.0375, 0.05, 0.06, 0.075 or 0.1 mg per day2 |
| Approved for | Preventing postmenopausal osteoporosis only1 | Hot flashes, vaginal atrophy, low estrogen from certain causes, preventing postmenopausal osteoporosis2 |
| How often | One patch once weekly1 | One patch once weekly2 |
| Where | Lower abdomen or upper buttock1 | Lower abdomen or upper buttock2 |
| Average estradiol level (Menostar label) | 13.7 pg/mL1 | Climara 6.5 cm2 (25 mcg a day): 24.7 pg/mL1 |
| Main label trial | 2 years vs placebo in women 60 to 80: spine bone density +2.99% vs +0.54%1 | Pooled trials vs placebo; side effects rise with dose2 |
| Notable side effects | Vaginal discharge 11% vs 1%; joint pain 12% vs 6%1 | Breast pain 5% to 29% by dose vs 4%; headache 5% to 18% vs 10%2 |
| Missed patch | Apply a new patch as soon as possible1 | Apply a new patch as soon as possible2 |
| Boxed warning | WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, PROBABLE DEMENTIA and BREAST CANCER1 | WARNING: ENDOMETRIAL CANCER, CARDIOVASCULAR DISORDERS, PROBABLE DEMENTIA and BREAST CANCER2 |
The Menostar label compares blood levels after one Menostar patch and one Climara 6.5 cm2 patch on the lower abdomen. Average estradiol was 13.7 pg/mL on Menostar vs 24.7 pg/mL on Climara, and peak levels 20.6 vs 37.2 pg/mL. The Menostar patch is 3.25 cm2 and holds 1 mg estradiol.1 The label quotes the Climara delivery rate (25 mcg a day) from the Climara labeling. It reports no trial of bone or symptoms against Climara.
Menostar's only use is bone. In its 2-year study of 417 women aged 60 to 80, spine bone density rose 2.99% vs 0.54% on placebo and total hip 0.84% vs a fall of 0.71%. Climara is started at 0.025 mg a day for every use, and for hot flashes or vaginal symptoms the dose is adjusted, with attempts to taper or stop every 3 to 6 months.12 Both labels say a woman with a uterus generally also needs a progestogen, and that non-estrogen medicines are considered first when the only goal is bone. These numbers come from separate trials with different people, lengths and methods, so they are not a head-to-head comparison.
Which, if either, fits is for your prescriber. More detail: Menostar side effects, Climara side effects, the Menostar and Climara dosing schedules and Climara vs Vivelle-Dot: how do the two estradiol patches differ?.