The patch is a form of contraception that is placed on the arm. You place the patch on the arm for a week at a time and you use 3 patches in a month’s time and then 1 week off and that’s when you have your cycle. The side effects of the patch include: some people have an allergy to the adhesive of the patch. Although this is not common, this can occur. The main concern about the patch is that it does have a higher profile risk of blood clot formation compared to all other forms of birth control.