Frequently Asked Questions

You want answers. We made it easy and put them all in one place.

The basics of Plan B

What is Plan B?

Plan B One‑Step is progestin‑only emergency contraception that helps prevent pregnancy before it starts when taken within 72 hours after unprotected sex.

Plan B is a backup method of preventing pregnancy and should not be used as regular birth control. Use as directed.

How effective is Plan B?

Plan B can significantly decrease the chance that you get pregnant. When used as directed, about 7 out of every 8 women who could have gotten pregnant did not become pregnant after taking Plan B.

Does Plan B work for women with a BMI over 25?

We hold the same belief as the FDA, which states that there are no safety concerns that preclude the use of levonorgestrel emergency contraceptives in women generally, and continue to believe that all women, regardless of how much they weigh, can use these products to prevent unintended pregnancy following unprotected sex or contraceptive failure. The most important factor affecting how well emergency contraception works is how quickly it is taken. When emergency contraception is taken as directed within 72 hours after unprotected sex or birth control failure, it can significantly decrease the chance that a woman will get pregnant. In fact, the earlier the product is taken after unprotected intercourse, the better it works. Emergency contraception is not 100% effective, which is why it is critical that women have a “Plan A” (regular) birth control method or start one if they don’t have one. If you have any further questions, we encourage you to talk to your healthcare provider.

How does Plan B work?

Plan B helps prevent pregnancy by temporarily delaying ovulation. That is, it works by stopping the release of an egg from the ovary, so there’s no egg to meet the sperm. No egg, no fertilization, no pregnancy.

Will Plan B affect my fertility or ability to get pregnant in the future?

Plan B will not impact your ability to get pregnant in the future.

What happens if I’m already pregnant and I take Plan B?

Plan B is not an abortion pill and it will not be effective if a woman is already pregnant. Plan B will not harm an existing pregnancy.

Can I continue to take my regular birth control after taking Plan B?

Yes! Plan B does not impact the effectiveness of any regular birth control methods, so you can continue your regular birth control right away—or start one, if you don’t have a regular method.

Taking Plan B

When should I use Plan B?

Plan B is emergency contraception you can take after:

  • You didn’t use any form of birth control or had unprotected sex
  • There was an issue with your regular birth control method (eg, the condom broke or slipped)
  • You missed a dose (or more) of your regular birth control pill

Use the countdown calculator

How soon after unprotected sex should I take Plan B?

You can take Plan B up to 72 hours (3 days) after unprotected sex. The sooner it’s taken after unprotected sex, the better it works.

How do I take the Plan B pill / Can I take Plan B with food and/or water?

Plan B One‑Step is one pill that you place in your mouth and swallow, preferably with water. You can take Plan B with or without food. The most important thing to know about taking Plan B is that it must be taken within 72 hours (3 days) after unprotected sex to help prevent pregnancy before it starts. The sooner you take it, the better it works.

Can I take Plan B if I’m breastfeeding?

Yes, you can use Plan B when you are breastfeeding. In general, no harmful effects of progestin‑only pills, like Plan B, have been found on breastfeeding performance or on the health, growth, or development of the infant. However, random cases of decreased (less) milk production in mothers have been reported.

How often can I take Plan B? Is there a limit to how many times you can take Plan B in a year/lifetime?

Plan B emergency contraception should not be used as a regular method of birth control. However, if you have already used Plan B, it can be safely used again after another instance of unprotected sex or birth control failure. It will not affect a woman’s future fertility.

Plan B doesn’t provide long-term protection against future pregnancy—it works to help prevent pregnancy after only one act of unprotected sex or birth control failure.

I had another incident of unprotected sex the day after taking Plan B. Am I still covered?

Plan B only stays in your body for a short amount of time. It doesn’t provide long‑term protection against future pregnancy; when taken as directed it works to help prevent pregnancy after only one incident of unprotected sex. If you are sexually active, even occasionally, see your healthcare professional or visit a family planning center/clinic to find a regular method of birth control that suits you.

Find a Family Planning Clinic

When is it not appropriate to use Plan B?

Do not take Plan B:

  • If you’re already pregnant, because it won’t work
  • If you’re allergic to levonorgestrel or any of the ingredients in Plan B
  • In place of regular birth control
  • If you’re male

This product is not intended for use in postmenopausal women.

Use before the first menstrual period is not appropriate.

What are the possible side effects of Plan B?

When used as directed, Plan B is safe and effective.

Some women may experience side effects, including:

  • a period that’s lighter, heavier, early, or late
  • nausea
  • lower abdominal cramps
  • tiredness
  • headache
  • dizziness
  • breast tenderness
  • vomiting

Some women taking Plan B may have changes in their period, such as spotting or bleeding before their next period. If your period is more than a week late, it’s possible you might be pregnant. Get a pregnancy test and follow up with your healthcare professional.

If you vomit within 2 hours of taking Plan B, talk to your healthcare professional to find out if you should repeat the dose.

Do certain medications affect how well Plan B works?

Examples of drugs or herbal products that could decrease the effectiveness of Plan B include barbiturates, bosentan, carbamazepine, felbamate, griseofulvin, oxcarbazepine, phenytoin, rifampin, St. John’s wort, topiramate, and certain HIV/AIDS medications.

Contact your healthcare professional before taking Plan B if you have any concerns or are taking any of these medications.

Getting Plan B

Do I need a prescription to get Plan B?

No. You can find Plan B yourself in the family planning aisle—no prescription or ID needed. There’s also no age requirement—anyone can buy it.

Do any states have restrictions on buying Plan B?

No. Plan B is available for purchase in every state—no prescription or ID needed. There’s also no age requirement. Anyone can buy it.

Where can I buy Plan B?

You can find Plan B yourself in the family planning aisle of all major retailers, including CVS, Walgreens, Rite Aid, Target, and Walmart. It’s also available at smaller pharmacies and some food stores around the country. Click here to find a store near you.

Prefer to order Plan B online? You can buy it directly from our site.

Remember, Plan B must be taken within 72 hours (3 days) after unprotected sex. If you need it right away, you can get it right off the shelf at the stores above.

Can I buy Plan B online?

Yes. Plan B is available online here.

Remember, Plan B must be taken within 72 hours (3 days) after unprotected sex. If you need it right away, you can get it right off the shelf at local retailers. Wondering where Plan B is stocked in your area? Find a store near you.

Is there any way to save on Plan B?

There are two ways to save on Plan B: a coupon or a rebate. Click here for how to save. Offers cannot be combined.

How do I talk to my friend, family member, or partner about taking Plan B?

Not sure how to bring up the topic of taking Plan B? Try the tips below.

  • Start with the facts. This site is full of information to help you have a conversation about Plan B—whether it’s with a friend, family member, or partner.
  • Plan ahead. Consider making a list of what you want to discuss and try practicing the conversation out loud. Think about potential responses to any concerns your friend/family member/partner might have.
  • Find the right time and place. Make sure you have a private place to discuss Plan B—a place where you won’t get interrupted or feel rushed.
  • Be respectful. Respect what the other person is thinking and feeling. Be open to other opinions, but remember: it’s your body and your choice.
  • Practice safe sex. Discuss future contraception. Safe sex is important, even if you’re in a monogamous relationship (remember: neither birth control pills nor emergency contraception like Plan B protect against STDs or HIV/AIDS).
What other resources can I turn to for information about Plan B and emergency contraception?

You can find downloadable PDFs, fact sheets, and more from Plan B on our resources page.

Check out the websites below to stay informed on what’s happening in women’s healthcare, and to learn more about birth control options and emergency contraception.

Planned Parenthood

Emergency Contraception Website (Princeton)

Mayo Clinic

Henry J. Kaiser Family Foundation

National Family Planning & Reproductive Health Association

Find a Family Planning Clinic

Foundation Consumer Healthcare is not responsible for the content on the websites listed above and disclaims any liability for the content of any page or site listed above.
Although the information above may be useful, it shouldn’t replace the advice of your healthcare professional. For questions about birth control and other women’s health issues, please talk to your healthcare professional.