Where can once weekly estrogen patches be applied?

Application Sites for Once-Weekly Estrogen Patches

Once-weekly estrogen patches can be applied to the abdomen, upper torso (back), upper outer arm, or buttocks. 1

Approved Application Sites

The following sites are appropriate for transdermal estrogen patch placement:

• Abdomen (lower abdomen specifically) 1, 2
• Upper torso (back) 1
• Upper outer arm 1
• Buttocks 1

Site Selection Considerations

Buttocks vs. Abdomen

The buttocks may provide superior absorption compared to the abdomen. Research demonstrates that buttock application results in 125% higher peak plasma concentrations and 117% greater bioavailability compared to abdominal application. 3 This enhanced absorption may be advantageous for women experiencing breakthrough symptoms at the end of the weekly wear period. 3, 4

Upper Arm Considerations

The upper outer arm delivers significantly higher systemic exposure than the abdomen or buttocks. Studies show 31% higher estradiol exposure and 24% higher progestin exposure when patches are applied to the arm versus the abdomen. 5 While this difference is unlikely to be clinically significant for safety, it should be considered when troubleshooting inadequate symptom control or excessive side effects. 5

Application Guidelines

Apply patches to clean, dry, intact skin at the chosen site. 2 The skin should be free of:

• Lotions or creams
• Oils or powders
• Irritation or broken areas
• Excessive hair 2

Rotate application sites to minimize local skin irritation, though patches can remain on the same general body area (e.g., alternating sides of the buttocks). 1

Common Pitfalls to Avoid

• Do not apply to the breasts - this site is not approved and should be avoided 1
• Avoid areas with skin folds or excessive movement that may compromise adhesion 1, 6
• Do not apply immediately after bathing - wait until skin is completely dry 2
• Avoid tight-fitting clothing over the patch site that may dislodge it 1

Skin Tolerability

Skin irritation occurs in approximately 6-8% of users and is the most common reason for discontinuation. 6 The 7-day patches demonstrate comparable irritation rates to twice-weekly patches but superior adhesion. 4, 6 If persistent irritation develops, rotating between the four approved application sites may improve tolerance. 1