[medical citation needed] The patch is a simple and convenient form of birth control that requires weekly attention.

The most frequent adverse events leading to patch discontinuation were: nausea and/or vomiting (2.4%), application site reaction (1.9%), breast discomfort, engorgement or pain (1.9%), headache (1.1%), and emotional lability (1.0%).

[12] Overall, side effects that tend to go away after two or three months include bleeding between periods, breast tenderness, and nausea and vomiting.

[medical citation needed] Symptoms that may last longer include skin irritation around the area where the patch is placed and a change in the woman's sexual desires.

[medical citation needed] However, despite the interactions with many other antibiotics, a clinical pharmacokinetic drug interaction study showed that oral administration of tetracycline HCl 500 mg for three days prior to and seven days during use of Ortho Evra "did not reduce effectiveness of Ortho Evra."

This is a significant factor in the common decision to administer tetracycline-derived antibiotics following an abortion (preventatively to fight potential infection) when synthetic hormone contraceptives are to be used afterwards.

[5] All combined hormonal birth control products have a very small increased risk of serious or fatal thromboembolic events.

There is ongoing research into the thromboembolic risks of Ortho Evra as compared to combined oral contraceptive pills.

In studies with oral contraceptives, the risk for cardiovascular disease (such as thromboembolism) is significantly increased in women over the age of 35 years who also smoke tobacco.

According to the manufacturer, the patches introduce a 60% higher level of estrogen into the bloodstream as compared to oral contraceptives; however, the clinical significance of this difference is unknown.

[5][8] The patch has been associated with strokes and thrombosis and the mechanism for hormone absorption and dissipation from the body's tissues is different from "the pill".