How to prescribe a 100mcg estradiol patch?

How to Prescribe a 100mcg Estradiol Patch

Prescribe a 100mcg (0.1mg) estradiol transdermal patch to be applied twice weekly (every 3-4 days) to clean, dry skin on the buttocks, abdomen, or upper outer arm, avoiding the breasts, and always add endometrial protection with oral medroxyprogesterone acetate 10mg daily for 12-14 days every 28 days if the patient has an intact uterus. 1

Prescription Details

Patch Application Instructions

• Apply one patch twice weekly (change every 3-4 days, typically on the same two days each week, such as Sunday and Wednesday) 2
• Application sites: Rotate between buttocks, abdomen, or upper outer arm; avoid breasts and waistline where clothing may rub 2
• Skin preparation: Apply to clean, dry, intact skin; avoid areas with cuts, irritation, or recent lotion application 2
• Each patch delivers 100mcg (0.1mg) estradiol per day and maintains therapeutic estradiol plasma levels of approximately 66 pg/ml 3

Critical Endometrial Protection Requirements

For patients with an intact uterus, you must prescribe concurrent progestogen therapy to prevent endometrial hyperplasia and cancer. 1, 2

Recommended Progestogen Regimens:

• First-line: Oral medroxyprogesterone acetate 10mg daily for 12-14 days every 28 days (sequential dosing) 1
• Alternative: Oral micronized progesterone 200mg daily for 12-14 days every 28 days if sequential dosing is preferred 4
• For continuous dosing: Oral micronized progesterone 100-200mg daily every day without breaks provides full endometrial protection long-term 5

Important caveat: A 5% incidence of endometrial hyperplasia was observed in one study when estrogen patches were used without adequate progestogen supplementation, emphasizing the absolute necessity of adding progestogen in women with an intact uterus. 2

Pre-Treatment Requirements

Baseline Assessment

• Perform transvaginal ultrasound to document baseline endometrial thickness before initiating therapy 4, 1
• Screen for contraindications to estrogen therapy, including history of venous thromboembolism, breast cancer, unexplained vaginal bleeding, and active liver disease 6

Expected Outcomes and Counseling Points

Bleeding Patterns

• With sequential progestogen: Expect predictable withdrawal bleeding after each 12-14 day progestogen cycle, typically lasting 5-6 days 7
• With continuous progestogen: Breakthrough bleeding is common in the first 3-6 months but decreases with continued use; amenorrhea rates improve over time 5

Symptom Relief

• Hot flushes: Expect significant reduction (>70% improvement) within 4 weeks of treatment 2
• Estradiol levels: The 100mcg patch achieves average plasma estradiol concentrations of 66 pg/ml, which are in the physiologic range for premenopausal women 3

Monitoring Strategy

Follow-Up Schedule

• If breakthrough bleeding persists beyond 6 months on continuous dosing, perform endometrial assessment rather than automatic dose adjustment 5
• Consider annual endometrial thickness monitoring if using off-label vaginal progesterone regimens 1

Common Pitfalls to Avoid

• Never prescribe estrogen alone to a patient with an intact uterus—this is the most critical error and significantly increases endometrial cancer risk 2
• Progestogen must be given for at least 12-14 days monthly in sequential regimens to provide adequate endometrial protection; shorter durations are insufficient 1
• Patch adhesion issues: If a patch detaches for <48 hours, apply a new patch immediately and keep the same change day; if ≥48 hours, apply a new patch and use backup contraception for 7 days if using for contraceptive purposes 6