Norelgestromin/ethinyl estradiol patch (Ortho Evra) May Increase Blood Clot Risk
September 21, 2006
The FDA and Ortho-McNeil issued a drug alert concerning increased risk of non-fatal venous thromboembolism (VTE) with the Ortho Evra patch (norelgestromin/ethinyl estradiol, 35 micrograms). A recent epidemiologic study reported a two-fold increased risk of VTE with Ortho Evra compared to oral contraceptives containing 35 micrograms of ethinyl estradiol and norgestimate. However, another epidemiologic study with analogous comparative groups found a similar risk of VTE in both groups. The FDA requested longer follow-up of the first study to assess the validity of the increased risk.
Estrogen exposure has been associated with increased VTE risk. Transdermal estrogen exposure from Ortho Evra results in 60% higher total estrogen concentrations in blood than similar oral estrogen doses. This increased estrogen exposure may contribute to the increased risk of VTE.
Educate current and potential Ortho Evra users on the risks associated with use of the patch. Advise patients to consult their health care provider if they would like to switch from Ortho Evra to an oral contraceptive. Ortho Evra users experiencing symptoms of VTE should discontinue use immediately.
Additional information is available at the following links:
- MedWatch alert:
- Updated Prescribing Information:
- Ortho Evra Questions and Answers:
- Drug Information Page:
September 21, 2006; University of Utah, Drug Information Service. Copyright 2009, Drug Information Service, University of Utah, Salt Lake City, UT.