Plan B tablets contain the medicine levonorgestrel, a female hormone that prevents ovulation (the release of an egg from an ovary). This medication also causes changes in your cervical mucus and uterine lining, making it harder for sperm to reach the uterus and harder for a fertilized egg to attach to the uterus.
Plan B is used to prevent pregnancy after unprotected sex or failure of other forms of birth control (such as condom breakage, or missing 2 or more birth control pills).
Next Choice, Plan B, Plan B One-Step
Heavy or light menstrual bleeding
Incidence not known
Absent missed or irregular menstrual periods
pain in the pelvis
stopping of menstrual bleeding
Some levonorgestrel side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:
Abdominal or stomach pain
tenderness of the breasts
unusual tiredness or weakness
Yaz (drospirenone and ethinyl estradiol) prevents ovulation (the release of an egg from an ovary) and also cause changes in your cervical and uterine lining, making it harder for sperm to reach the uterus and harder for a fertilized egg to attach to the uterus. Yaz is used as contraception to prevent pregnancy. It is also used to treat moderate acne in women who are at least 14 years old and have started having menstrual periods, and who wish to use birth control pills to prevent pregnancy. Yaz is also used to treat the symptoms of premenstrual dysphoric disorder (PMDD), such as anxiety, depression, irritability, trouble concentrating, lack of energy, sleep or appetite changes, breast tenderness, joint or muscle pain, headache, and weight gain.