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"If I took the Plan B pill two days in a row will they cancel each other out?"

ZocdocAnswersIf I took the Plan B pill two days in a row will they cancel each other out?


If I took the Plan B pill two days in a row will they cancel each other out?


I recommend that you visit an Obstetrician/gynecologist to discuss your concerns. Plan B or levonorgestrel, is used for emergency contraception following unprotected intercourse or possible contraceptive failure. Plan B works by several mechanisms: preventing sperm from traveling through the uterus, inhibition of ovulation, and inhibition of implantation of a fertilized egg. It is not effective after implantation has begun. Plan B comes in two regimens, a single dose and a two-dose. You should follow the instructions on the packaging in regards to taking the pill. Known side effects of Plan B include fatigue, headache, dizziness, heavy menstrual bleeding, light menstrual bleeding, breast tenderness, nausea, abdominal pain, vomiting, and diarrhea. Plan B is contraindicated if you are already pregnant and does not provide protection against sexually transmitted infections. In addition, Plan B will not terminate an existing pregnancy. Generally speaking, taking an additional dose will not cancel out the effects of the initial dose, but you should take the pill as directed on the packaging. You should use barrier contraception (ie. condoms) immediately after taking Plan B. Fertility returns quickly after taking the pill. If you normally take oral contraceptive pills, patch, or ring, these may be used after taking the pill. You should consider seeing an Obstetrician/gynecologist for advice and options regarding contraceptive measures including male and female condoms, diaphragms, oral contraceptive pills, and intrauterine devices.

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