What is the name of the once a week estrogen (estrogen replacement therapy) patch?

Once-Weekly Estrogen Patch Options for Estrogen Replacement Therapy

The once-weekly estrogen patch for estrogen replacement therapy is called Climara (estradiol transdermal system). This patch delivers 17β-estradiol continuously for a full 7-day period 1.

Available Formulations and Dosing

Climara is available in different dosage strengths:

• Patches releasing 50 μg of 17β-estradiol daily
• Patches releasing 100 μg of 17β-estradiol daily

There is also a combination product called Climara Pro that contains both estradiol and levonorgestrel (a progestin) for women who need both hormones 2, 3.

Application Instructions

• The patch should be applied to clean, dry skin on the:

  • Abdomen
  • Upper torso
  • Upper outer arm
  • Buttocks 1

• Research indicates that application on the buttocks may provide slightly higher absorption (about 17-25% higher) compared to abdominal application, which may be beneficial for women who experience menopausal symptoms toward the end of the weekly cycle 4.

Administration Schedule

The patch is designed to be:

• Applied once weekly
• Worn for 7 consecutive days
• Replaced with a new patch after 7 days 1, 5

Clinical Efficacy

Climara has been shown to:

• Maintain sustained blood levels of estradiol for the full 7 days of patch wear
• Maintain a physiologic estrone to estradiol ratio
• Significantly decrease the frequency of hot flashes compared to placebo
• Provide comparable efficacy to oral conjugated equine estrogens
• Begin showing effectiveness within 1-2 weeks after starting therapy 5

Advantages of Transdermal Delivery

The transdermal route offers several benefits:

• Avoids first-pass hepatic metabolism
• Provides more stable hormone levels
• May have a better cardiovascular risk profile than oral estrogens
• Particularly beneficial for women with iatrogenic premature ovarian insufficiency or those at increased cardiovascular risk 1

Common Side Effects and Considerations

• Local skin reactions (erythema, irritation) occur in approximately 6.8% of users
• The patch has excellent adhesion properties compared to some other transdermal systems
• No evidence of drug accumulation with continuous use 5

For women who need both estrogen and progestin therapy, the combination patch Climara Pro provides both hormones in a single weekly application 2, 3.