Plan B Side Effects

What Is Plan B and How Does It Work?

Plan B, or the morning After Pill: We've all heard of it, some of us have used it, but how does plan B work, exactly? How effective is it and how much does it cost? The Plan B pill is designed to be used within 3 days of intercourse, though it is most effective when used the "morning-after" potential birth control failure or unprotected sex (within 24 hours). This medication is not designed to be routine birth control; Instead, doctors and pharmacists recommend it for emergency situations only. Here's what you need to know about how it works and plan b side effects.

Disclaimer: The following is intended for educational purposes only. We are not doctors so please do not read the following content as such. If you have any questions about emergency contraception, your health, or are seeking medical advice, please speak with your gynecologist.

9 Facts About Plan B:

  1. It can be taken up to 72 hours after intercourse, though it is more effective within 24 hours.
  2. Effectiveness ranges from approximately 95% effective if taken within 24 hours of intercourse or 89% if taken within 72 hours.
  3. The morning-after pill is available over-the-counter to women 17+ years of age in the United States, or by prescription for minors.
  4. Plan B Side effects may include heavier menstrual bleeding, lower abdominal pain, headaches, fatigue, dizziness, and nausea.
  5. Plan B is only one name for emergency contraception. There are other brands such as My Way, AfterPill, and Take Action. These also contain Levonorgestrel.
  6. Typically, it costs between $40 and $50 in a drug store. My Way may cost less ($20-$45) and AfterPill (the generic brand) is available online for $20 without shipping costs.
  7. It will not terminate an existing pregnancy.
  8. Emergency contraception is not designed to be used as birth control.
  9. Birth control may have higher rates of effectiveness if used consistently.

What Is the Plan B Pill?

Also known as the Morning After Pill, it's one of the most common forms of emergency contraception. This means that it's designed to be used after unprotected sex to reduce the risk of pregnancy. It is not designed to be routine contraception, otherwise known as birth control.

Plan B contains two tablets: One to be taken as soon as possible following unprotected sex (within 72 hours), and the second to be taken 12 hours following the initial dose.

How Common Is Emergency Contraception Use?

According to data from the Centers for Disease Control and Prevention, 11% of American women used emergency contraception between 2006 and 2010. That's 5.8 million women who admit to using something like the Plan B pill, the copper IUD, or the Ella pill. Among younger women (ages 20 to 24), use was ever more prevalent: close to a quarter of women had used it.

Why do most women use emergency contraception? The CDC reports that approximately half use it due to concern that their birth control method has failed. Half have reported using it following unprotected sex.

How Does Plan B Work?

The Morning After pill contains a hormone called Levonorgestrel, which is shown to prevent pregnancy after sex. More specifically, a tablet contains 1.5 mg of Levonorgestrel, which has a half-life of around 24 hours, according to research on its efficacy.

Levonorgestrel is not only used in the morning-after pill. It's also used in lower doses in several hormonal birth control methods, including IUDs Liletta and Miren. Plan B is not the only form of emergency contraception that contains Levonorgestrel. Others include My Way and the AfterPill, both of which may be more affordable than Plan B.

What does Plan B do exactly? It may stop an egg from being released or prevent the fertilized egg from reaching the uterus. None of these include abortion. The morning-after pill will not stop an existing pregnancy.

How Effective Is Plan B?

Morning-after pills are said to range between 95% and 89% effective according to, dependent on whether it is taken within the first 24 or 72 hours. However, some research finds them to be more effective: One study discovered that the subjects who took emergency contraception containing Levonorgestrel within 72 hours had a pregnancy rate of 2.6%. That would make the medication they took 97.4% effective.

Though the Plan B pill may be the most available form of emergency contraction, it is not the most effective. Research, including the study cited above, has found that the copper IUD is the most effective form of emergency contraception. More specifically, one study found that the pregnancy rate following copper IUD insertion as a form of emergency contraception was 0.1%.

The second most effective form of emergency contraception is a medication that contains ulipristal acetate as opposed to Levonorgestrel. More specifically, the Ella pill contains ulipristal acetate rather than Levonorgestrel like Plan B and other alternatives. Research has found that pregnancy rates in cases of using ulipristal acetate an emergency contraception rage from 0.9% to 2.1% -- putting it at 97.9-99.1% effective.

Ulipristal acetate is typically available through prescription and Levonorgestrel options such as the Plan B Pill are available over the counter for women over 17 years of age. The Copper IUD must be inserted by a clinician. Keep in mind that none of these options function on preexisting pregnancies.

How Much Is Plan B?

Typically, costs range between $40 and $50. There are cheaper options available, such as generic emergency contraception pills (My Way, AfterPill, and Take Action). Additionally, several retailers (which may include the medication's website), offer Plan B coupons. This could bring the cost down to under $20, though prices vary depending on your state and pharmacy of choice. The lowest price for brand name Plan B that the EverCup staff has observed is $15.76 (after using a coupon) from Stop n Shop.

6 Plan B Side Effects

Several Plan B Side effects have been observed in clinical trials. Note: If vomiting occurs within 2 hours of use, please contact your physician. According to data from the FDA, typical side effects may include:

  1. Heavier period flow
  2. Lower abdominal pain
  3. Fatigue
  4. Nausea
  5. Headaches
  6. Dizziness

Experiencing heavier menstrual bleeding is the most common symptom. Approximately 31% of people surveyed in data cited by the FDA experienced it after taking emergency contraception.

Emergency Contraception, Explained

More women than ever are using Plan B, other morning-after pills and other forms of emergency contraception like the copper IUD. In other words, contraception is becoming more normalized than ever. However, that does not mean that emergency contraception should be used long term or as a replacement for birth control. Not only are they not designed for long-term use, but Plan B side effects are common and the price tag can be significant. Please contact your gynecologist to learn more about healthful, longterm and effective birth control options.

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