How to Use the Plan B Morning-After Pill (2024)

Plan B One-Step is the brand name ofan oral hormone pillapproved by the U.S. Food and Drug Administration (FDA) in 2009as an effective form ofemergency contraception. Also known as the "morning-after pill," PlanB One-Step is used to prevent pregnancy after unprotected sex.

Plan B One-Step consists of one pill containing 1.5 milligrams (mg) of the progestin hormone levonorgestrel. It replaces the original Plan B (sold under the generic nameNext Choice), in which two pills are taken.

If used as directed, Plan B One-Step and Next Choicecan reduce the risk of pregnancy by around 97%, according to a 2010 study in theLancet.

Levonorgestrel-only emergency contraceptives can be found on drugstore shelves under such brand names as Take Action, My Way, My Choice, Afterpill, and others.

How They Work

Plan B One-Step and Next Choicework in the same way as progestin-only birth control pills. They cause the mucus in the cervix to thicken,making it difficult forspermto enter theuterusand fertilize anegg. Levonorgestrel also thins the lining of the uterus, making it near impossible for an egg to implant even if fertilization were to occur.

While effective in preventing birth, a 2015 review inClinical Obstetrics and Gynecologyconcluded that the levonorgestrel tablets fell a bit short compared totwo other emergency contraceptive options approved by the FDA:

• Copper intrauterine devices (IUDs) are consideredthe most effective method overall with a failure rate of only 0.1%.
• Ella (ulipristal acetate) is aprogesterone agonistthat, in real-world testing, was 65% more effective than levonorgestrel in the first 24 hours after sex and 42% more effectivein the first 72 hours after sex.

Of the currently approvedoptions, combination progestin/estrogen pillswere the least effective overall, nearly doubling the risk of pregnancy versus levonorgestrel alone.

If takenwithin 72hours of unprotected sex, levonorgestrel can reduce your risk of pregnancy by around 89%. If takenwithin24 hours, it is around 97% effective.

How to Take Them

Although the package insert indicates that Plan B and Next Step are effective for72 hours after unprotected sex, a number of studies have suggested that they maywork for up to five days, albeit with declining efficacy. Clearly, the earlier you start treatment the better.

In the United States, progestin-only emergency contraception is available without a prescription for women 17 and over. You may need to bring some form of ID to prove your age.

If you are under 17, you would need to get a prescription.Most Planned Parenthood centers, women's health clinics, and hospital emergency rooms canprovide both aprescription and the emergency contraceptive at the same time.

Plan B One-Stepusually costs around $50, while the generics cost about $40 or less. If you would like your health insurance to pay for it, ask your pharmacist for help in submitting a claim.

The dosing instructions for Plan B and Next Step are pretty straightforward;

• For Plan B One-Step, take one 1.5-mg pill as soon as you can with or without food.
• For Next Step, you can either take both 0.75-mg pills at the same time or in a divided dose (taking the first pill as soon as you can, followed by the second pill 12 hours later).

Side Effects

Levonorgestrel is known to cause nausea in some women. To avoidvomiting the pill, take a dose of Kaopectate or Pepto-Bismol (both of which contain (bismuth subsalicylate) if you feel queasy or nauseous. You can also take an over-the-counter antinauseal likeBonine (meclizine), Dramamine (dimenhydrinate),or Valoid (cyclizine).

Other possible side effects include:

• Headaches
• Dizziness
• Breast tenderness
• Abdominal pain
• Spotting
• Changes in your flow(either heavier or lighter)
• A delayed or early period during your next menstrual cycle

Plan B or Next Step are not known to cause serious complications.

Interactions

There are some drugs that caninteract with Plan B and Next Stepby reducing the concentration of levonorgestrel in the blood. While most of these interactions won't undermine the efficacy of emergency contraception, the HIV drug Sustiva (efavirenz)can reduce levonorgestrel concentration by as much as 50%,according to a 2017 study in the journalAIDS.

If taking Sustiva or the combination HIV drug Atripla (which contains efavirenz), speak with your healthcare provider if emergency contraception is needed. A largerdose of Plan B or Next Step may be needed.

Never increase the dose of Plan B or Next Step unless yourpractitoner tells you to do so. Doing so can increase the risk of side effects, including heavy bleeding and vomiting.

Call your healthcare provider if youhave pregnancy symptoms, receive a positivehome pregnancy testresult, ordo not have a period for more than three weeks after taking an emergency contraceptive.

A Word From Verywell

Plan B One-Step or Next Step should not be used as your main form of birth control. The frequent use of progestin-based emergency contraception can cause your periods to become irregular and unpredictable. There are more cost-effective ways to prevent pregnancy than emergency contraceptives.

If unsure about your birth controloptions, speak with your healthcare provider or visit your nearest Planned Parenthood or women's health clinic.