Plan B vs. the Abortion Pill: What’s the Difference?

Plan B vs. the Abortion Pill: What’s the Difference?

Emergency contraceptives, also known as Plan B, are often confused with RU-486, otherwise known as the “abortion pill.” While they’re both actually pills and are taken as either a preventive or result of unplanned pregnancy, the two are very different. If you’re handling an unplanned pregnancy, it’s important that you know the differences so you can make the best choice for yourself and your health.



Listed below are the main differences in the two pills, when each is taken and common side effects.


Emergency Contraceptives

  • What it is: Plan B, sometimes also called the “morning after pill” is an over-the-counter emergency contraceptive that is taken relatively soon after unprotected sex or birth control failure. Taking the pill prevents a pregnancy from occurring – stopping the release of an egg and/or stopping the sperm from fertilizing the egg. If you are already pregnant, emergency contraceptives like Plan B will not work.
  • When you can take it: Up to 72 hours after sex, but within 24 hours is the most effective. Some may even work up to five days after sex, but really, the sooner you take it, the more effective it will be.
  • Some common symptoms and side effects:
    • Nausea
    • Dizziness
    • Fatigue
    • Headache
    • Lower abdominal cramps and/or pain
    • Heavier menstrual bleeding
  • Other things to consider:
    • Plan B is one type of emergency contraceptive. It’s usually used as a blanket name for all emergency contraceptives – but there are a few different options.
    • If you throw up shortly after taking Plan B, it’s possible that you have not digested the medication and will need to take it again.
    • If you are over 165 pounds, emergency contraceptives are less effective.



  • What it is: Mifeprex, also known as the “abortion pill” or RU-486, is taken after a pregnancy is confirmed through an ultrasound. This procedure is a two-pill process, one pill is taken at the doctor’s office and one is taken at home. The first pill will stop the hormone progesterone that is needed for growth of the fetus, and the second is taken up to 48 hours later that terminates the pregnancy like a miscarriage. Any time after taking the second pill, you will pass the tissue vaginally.
  • When you can take it: Up to 10 weeks after your last period, but the sooner, the more effective. It is usually recommended within eight weeks.
  • Some common symptoms and side effects:
    • Nausea/vomiting
    • Weakness
    • Infection
    • Dizziness
    • Blood Clots
    • Heavy bleeding and cramps
  • Other things to consider:
    • While Mifeprex is 98% effective taken in the first eight weeks, it does not work for everyone. If you are still pregnant after this procedure, a surgical abortion will be required.
    • It cannot be predicted when you will pass the tissue, but it usually will happen in two to three days. It can happen at any time of day.
    • This medication is only available from your doctor. You cannot buy it from a drugstore like emergency contraceptives.
    • Depending on insurance, lab work, offices visits and location, this procedure can cost anywhere from $300-$800.


If you’re experiencing unplanned pregnancy and would like more information about your options, schedule a free and confidential appointment with Her Health’s friendly and professional staff.




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