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The Plan B pill works best when you take it within 3 days after unprotected sex. Like all morning-after pills, take Plan B ASAP after unprotected sex. You can get Plan B at your local drugstore or pharmacy.

How effective is Plan B One-Step and other levonorgestrel morning-after pills?

A levonorgestrel morning-after pill — like Plan B One Step, Take Action, My Way, Option 2, Preventeza, AfterPill, My Choice, Aftera, and EContra — can lower your chance of getting pregnant by 75–89% if you take it within 3 days after unprotected sex.

You can take Plan B and other levonorgestrel morning-after pills up to 5 days after unprotected sex. But sooner is better — the longer you wait to take it, the less effective it is.

Levonorgestrel morning-after pills may not work if you weigh more than 165 pounds. If that’s the case, IUDs or ella are better options for you. Our handy quiz can help you figure out which EC is best for you.

Though there are many different brands of levonorgestrel morning-after pills, they all work the same way. All brands have the same amount of medicine and the same effectiveness, no matter how much they cost. They prevent pregnancy by delaying ovulation. Taking them ASAP gives you a greater chance of preventing pregnancy.

How do I use Plan B and other levonorgestrel morning-after pills?

Take levonorgestrel morning-after pills (like Plan B One-Step, Take Action, My Way, AfterPill, Aftera, and EContra) as soon as you can after unprotected sex. Simply swallow the tablet the way you would any other pill. Read the instructions that come in the package for more information.

You can take these morning-after pills up to 5 days after unprotected sex, but they work much better if you take them during the first 3 days.

Take a pregnancy test if you haven’t gotten your period within 3 weeks after taking the morning-after pill.

Don’t take Plan B One-Step or other levonorgestrel morning-after pills if you’ve taken ella in the last 5 days.

Does the Plan B morning-after pill have side effects?

The morning-after pill is super safe, and Plan B side effects aren’t super common. There have been no reports of serious problems out of the millions of people who’ve taken it.

After you take the morning-after pill, it's totally normal for your next period to be different from what you’re used to. It may come earlier or later, and be heavier, lighter, or more spotty. Or it may be the same as it normally is.

You may get a headache, upset stomach, feel lightheaded or dizzy, or have tender breasts for a short while when you take the morning-after pill. If you throw up within 2 hours of taking the pill, it won't work and you’ll need to take it again.

Where can I get the Plan B morning-after pill?

You can buy levonorgestrel morning-after pills (like Plan B One-Step, Take Action, My Way, Option 2, Preventeza, AfterPill, My Choice, Aftera, and EContra) over the counter without a prescription at drugstores and pharmacies. It doesn’t matter how old you are and it doesn’t matter what your gender is.  Sometimes the morning-after pill is locked up or kept behind the counter, so you may have to ask the pharmacist or store clerk for help getting it — but you don’t have to have a prescription or show your ID.

You can also get the morning-after pill at many family planning or health department clinics, and Planned Parenthood health centers.

How Much Does Plan B Cost?

Plan B One-Step usually costs about $40–$50. Generics like Take Action, My Way, Option 2, Preventeza, My Choice, Aftera, and EContra generally cost less — about $11–$45. You can also order a generic brand called AfterPill online for $20 + $5 shipping. (AfterPill can’t be shipped quick enough to use if you need a morning-after pill right now, but you can buy it and put it in your medicine cabinet in case you need it in the future.)

The brand of EC you buy or how much you pay for it doesn’t matter — all brand-name and generic levonorgestrel morning-after pills work just as well.

You may be able to get the morning-after pill for free or low cost from a Planned Parenthood health center, your local health department, or another family planning clinic. Call your nearest Planned Parenthood to see if they can help you get emergency contraception that fits your budget.

If you have health insurance or Medicaid, there’s a good chance you can get Plan B for free — you just have to ask your nurse or doctor for a prescription so your health insurance will cover them (even though you don’t need a prescription to buy these types of morning-after pills over-the-counter). The staff at your local Planned Parenthood health center can also help you figure out if your health insurance will pay for your morning-after pill. Read more about using health insurance to pay for emergency contraception. 

Since the morning-after pill works better the sooner you take it, it’s a good idea to get it BEFORE you need it.  You can keep it in your medicine cabinet and it will be there for you, just in case. That way you can take it as soon as possible if an accident happens, and you won’t have to worry about finding it at the store when you’re stressed out.

What medicines affect how well Plan B works?

These medicines or supplements can make Plan B and other levonorgestrel morning-after pills not work as well:

• The antibiotic Rifampin (other antibiotics don’t make Plan B less effective)

• The antifungal Griseofulvin (other antifungals don’t make Plan B less effective)

• Certain HIV medicines

• Certain anti-seizure medicines (these are sometimes also used to treat psychiatric disorders like bipolar disorder)

• The herb St. John’s Wort

You can ask a nurse, doctor, or pharmacist about any medications you’re taking, and they can help you figure out if Plan B is a good option for you.

More questions from patients:

Can emergency contraception delay period?

Emergency contraception can delay your period. In fact, getting your period later or earlier than usual is one of the most common side effects of emergency contraception pills like Plan B and ella.

It’s also pretty common to have some spotting in between taking emergency contraception and getting your period, or for your period to be lighter, heavier, or a little different than usual when you do get it.

However, if you don’t get your period within 3 weeks of taking emergency contraception, take a pregnancy test.

If you aren’t pregnant, your menstrual cycle should return to normal the next month. But using emergency contraception often can cause your periods to become irregular or unpredictable. That’s 1 reason why it’s better to use a regular birth control method instead of relying on emergency contraception. Plus, birth control methods like the IUD, implant, or pill (to name a few) are way better at preventing pregnancy.

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