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Plan B One-Step, also known as the morning-after pill, is an oral medication that can prevent pregnancy when people have sex without contraception. Plan B does not end an already established pregnancy and does not protect against sexually transmitted infections (STIs).

This article discusses Plan B One-Step, including effectiveness, potential side effects, and more.

Plan B One-Step (levonorgestrel) is an over-the-counter (OTC) emergency contraceptive approved by the Food and Drug Administration (FDA).

For best results, a person should take it as soon as possible after having sex without using a condom or other form of barrier birth control, or if contraception has failed.

How it works

According to the FDA, Plan B can work in two ways:

  • stopping the ovary from releasing an egg
  • preventing a fertilized egg from implanting in the uterus

As Plan B stops the ovaries from releasing an egg, the sperm has nothing to fertilize, and pregnancy will not occur. If sperm fertilizes an egg, Plan B One-Step prevents the fertilized implanting in the uterus, making pregnancy impossible.

However, if a fertilized egg implants in the uterus before a person takes Plan B, the medication will not work. Anyone who thinks they might be pregnant may consider speaking with their doctor.

Plan B One-Step is most effective when taken as soon as possible within the first 72 hours after having sex without using barrier contraception or contraception failure.

Plan B may be less effective in people near ovulation or with a higher body mass index (BMI).

Plan B is an oral tablet. A person should follow all instructions on the product and consult a healthcare professional if they have any questions.

Kaiser Permanente recommends that individuals take one tablet with or without food within 72 hours after having sex without a barrier method. If they vomit within 2 hours, a doctor can advise whether it is best to take another pill.

A person should inform their doctor if they have had unexplained vaginal bleeding before taking the Plan B pill.

It is best for a person to consult a doctor 3 weeks after taking levonorgestrel contraception. They can check that the pill has worked and the individual is not pregnant or experiencing any harmful effects.

Plan B or other levonorgestrel pills are not intended for regular birth control. According to the manufacturer, Plan B is safe to take while breastfeeding and typically does not affect breastmilk supply. However, anyone breastfeeding or chestfeeding should consider seeking medical advice before taking any of these drugs.

Emergency contraceptive pills work only after one episode of sex without a barrier method. That said, individuals who engage in sexual activity without any barrier methods in the same cycle should take the pill again.

According to Planned Parenthood, Plan B and other levonorgestrel morning-after pills are available without a prescription for persons of any age.

They can purchase it from an online provider or schedule collection at their local pharmacy.

The following are the platforms and companies that offer Plan B One-Step:

Please note that the writer of this article has not tried these products. All information presented is purely research-based and correct at the time of publication.

Medical News Today follows a strict product selection and vetting process. Learn more here.


Nurx is a company that stocks birth control medications and treatments for skin conditions, STIs, and herpes, among others.

The New Day pill, Plan B’s generic version, is available for $20 on the Nurx website.

Free ground shipping is available, and a person can also opt for an expedited delivery for an additional $15.

The company recommends that people request a prescription for Ella if they need the emergency contraception pill as soon as possible, as it comes with overnight shipping.

CVS Pharmacy

CVS Pharmacy sells the emergency contraception pill for $49.99 and allows customers to buy up to 6 packages.

It offers free shipping for CarePass members and those who spend $35 or more.

Rite Aid

The emergency contraception pill is available at Rite Aid pharmacy for $47.49, and it allows customers to pay through their flexible spending accounts (FSA) and health savings accounts (HSA).

Shipping is free with an order of $34.99.

Planned Parenthood

Individuals can obtain Plan B from a Planned Parenthood health center, and they can choose to attend their appointment in-person or online. A smartphone app is also available for Apple and Android users.

The website advises people to wear a cloth face covering for in-person appointments and reschedule their visit if they are experiencing shortness of breath, fever, or cough.


A person can buy Plan B One-Step from Walgreens for $49.99 and choose between collection and delivery orders.

The website accepts FSA payments, and it also offers free shipping when customers spend $35 or more.


Target stocks Plan B for $44.99 and accepts FSA and HSA payments.

People can also benefit from a 90-day return guarantee.

Plan B One-Step can cause side effects for some people. According to the FDA, some reported side effects include:

The most common side effect of Plan B One-Step is heavier menstrual bleeding. Otherwise, the FDA generally regards the medication as safe. In addition, people who are breastfeeding or chestfeeding can use the medication without adverse effects.

Plan B interactions with other medications

A person considering Plan B should talk with their doctor if they take other medications. The following medications reduce the effectiveness of Plan B:

According to Kaiser Permanente, a person should keep a record of nonprescription and prescription drugs they use, as well as herbal products. They should share this record with their doctor and pharmacist.

Learn more about drug interactions here.

Plan B One-Step can provide the most effective birth control when taken within 12 hours of sex without a barrier method. Plan B suggests that the sooner a person takes the medication, the better it will work.

However, a person should not use the medication as their primary form of birth control.

An individual has several birth control options. Reversible birth control options include:

In some cases, a person may want a more permanent solution. A person with female reproductive organs can have a tubal ligation, in which a doctor will remove or block the fallopian tubes.

A person with male reproductive organs can have a vasectomy, in which a doctor will block or remove the tubes that transport sperm. Though often referred to as permanent procedures, doctors can reverse them in most cases.

A person may use a different form of emergency contraceptive if they prefer. Some generic versions that are effective as Plan B when people take them within 72 hours of sex without a barrier method include:

  • My Way: According to the manufacturer, a person should take My Way as soon as possible after engaging in sexual activity without any barrier methods. Those who experience severe abdominal pain should seek immediate medical attention, as they may have an ectopic pregnancy. In addition, this pill can change a person’s next expected period.
  • Next Choice One-Dose: This is available without a prescription and requires people to take it within 72 hours of sex without a barrier method. It may not be very effective for those who weigh more than 160 lb.
  • Take Action: A person can take this within 72 hours after engaging in sex without a barrier method to reduce the chance of pregnancy. According to the National Library of Medicine, a person should not use Take Action as a regular birth control method or if they are already pregnant. Also, this pill can cause menstrual changes, tiredness, and breast pain, among others.

Learn more about the Take Action emergency contraception pill here.

A person may also wish to take Ella, the branded version of ulipristal acetate. It can reduce a person’s chance of getting pregnant by 85% if they take it within 5 days after having sex without using a barrier method. It is available with a prescription.

Learn more about the morning-after pill here.

People should not use the Plan B One-Step as a regular birth control pill. They should discuss with their doctor if they are interested in learning more about regular birth control and suitable options for them.

Planned Parenthood also recommends that individuals ask a doctor to determine if Plan B is safe for them. This is because levonorgestrel morning-after pills may not work if a person is taking other medications, including some HIV drugs and antiseizure medications.

The following are some common questions about Plan B One-Step.

How long do I have to take Plan B?

Plan B is a single-dose tablet. A person can take the tablet for up to 72 hours after sex without a barrier method, but sooner is better.

Ideally, a person would take Plan B as soon as possible after having sex without using barrier contraception or having concerns that their contraception failed.

How much does Plan B cost?

Prices can vary for Plan B. A person can purchase Plan B One-Step for around $50 online, or it may be cheaper with a prescription.

However, it may be best to purchase the medication at a local pharmacy due to its time-limited effectiveness.

Does health insurance cover Plan B?

Plan B One-Step is an OTC medication. This means that most insurance companies will not cover the costs. A person may be able to use their HSA or other medical savings to purchase the medication.

How do I know if Plan B did not work?

A person may be pregnant if their period is more than a week late or they have not had it within 3 weeks of taking Plan B. People should speak with their doctor and take a pregnancy test.

Plan B One-Step is a single-dose emergency contraceptive. A person should not use it in place of regular birth control methods. The medication is most effective when taken within the first 72 hours after a person has sex without contraception or if there is a risk the contraception has failed.

Plan B does not protect against STIs or other conditions and will not end an already established pregnancy.