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Here are 11 questions and answers on the emergency contraceptive Plan B and its FDA approval for over-the-counter sales to women aged 18 and older.
1. What is Plan B?
Plan B is an emergency contraceptive pill taken by mouth after unprotected sex. It is used to prevent pregnancy. It is not for routine contraceptive use and does not prevent against sexually transmitted diseases, including HIV.
2. How is Plan B taken?
Plan B should be taken within 72 hours of unprotected intercourse. When taken within 72 hours, it decreases the chance of getting pregnant by 89% -- from 8% without Plan B to 1% with Plan B.
It's even more effective when taken within 24 hours. Effectiveness decreases the longer a woman waits to take it.
3. Who may buy Plan B over the counter?
Women aged 18 and older. Although available over the counter, Plan B will be kept behind the pharmacy counter. Women will need to ask the pharmacy staff for Plan B and may need to show proof of age.
4. What about younger women?
Women aged 17 and younger can still get Plan B by prescription.
5. Why is there an age restriction for Plan B's over-the-counter sales?
The FDA says they wanted to treat it like other prescription products, such as nicotine- replacement products, that require that age. They thought for this program to work, age 18 made sense.
6. When will Plan B become available over the counter?
Barr Pharmaceuticals, Plan B's maker, plans to introduce over-the-counter sales of Plan B to women aged 18 and older by the end of 2006.
7. What is Plan B's active ingredient?
Each Plan B pill contains 0.75 milligrams of levonorgestrel, a synthetic version of the hormone progestin.
Levonorgestrel has been used in birth control pills for over 35 years. Plan B contains a higher dose and is taken as two separate doses 12 hours apart.
8. Is Plan B a new drug?
No. It's been available by prescription to all women since 1999.
Plan B has never before been sold over the counter in the U.S.
9. How does Plan B work?
Plan B works like other birth control pills to prevent pregnancy. Plan B acts primarily by stopping the release of an egg from the ovary. It may prevent a sperm from fertilizing the egg.
If fertilization does occur, Plan B may prevent a fertilized egg from attaching to the womb. If a fertilized egg is implanted prior to taking Plan B, Plan B will not work and pregnancy proceeds normally.
10. Does Plan B have any side effects?
Like any medication, Plan B does have side effects. The most common side effect is nausea, which occurs in about a quarter of women after taking Plan B. Other side effects include abdominal pain, fatigue, headache, and heavy menstrual bleeding.
11. Is Plan B the same as RU-486?
No. RU-486, sold as Mifeprex, is a prescription drug for medical abortion. Mifeprex is used after a woman is already pregnant. Plan B is an emergency contraceptive. It is used to prevent pregnancy. While some people do feel that pregnancy begins at the time of conception, many doctors and the FDA do not describe Plan B as an abortion pill but as emergency contraception.
Published Aug. 24, 2006.
SOURCES: News release, Barr Pharmaceuticals. FDA: "FDA's Decisions Regarding Plan B: Questions and Answers," May 7, 2004. Steven Galson, MD, MPH, director, FDA's Center for Drug Evaluation and Research.