What to Know About the 'Morning-After' Pill

Plan B is the brand name of a type of emergency hormonal contraception pill that is taken orally to significantly reduce the chances of pregnancy after unprotected sex.

It can go by other names, such as the morning-after pill, emergency contraception or levonorgestrel.

Plan B's dosage used to be two 0.75 milligram (mg) pills taken orally, but it has been mostly replaced by Plan B One-Step, which is one 1.5 mg pill. If a patient is given the original form of two pills, it is advised they take them both at the same time.

Other brand names for pills containing levonorgestrel include Take Action, My Way, Option 2, Preventeza, AfterPill, My Choice, Aftera and EContra. There can be differences in price between brands when buying them from a pharmacy or online.

How Plan B works

"Plan B works like other birth control pills to prevent pregnancy," said Monica Grover, D.O., an OB-GYN and the chief medical officer at VSPOT, a women's intimate care clinic in New York City.

It is a backup method of birth control that works primarily by preventing egg release from the ovary, but it can also stop a fertilized egg from attaching to the womb, which is known as implantation, she explained.

It has a 75 percent to 89 percent effectiveness rate of preventing pregnancy if taken within three days of intercourse. Even though it can be taken up to 72 hours after sex, it is considered more effective the earlier it is taken.

The morning-after pill is widely considered to be safe to take while breastfeeding. If you are already pregnant, it will not affect the pregnancy, according to a study published in Fertility and Sterility journal.

Where is Plan B available?

Plan B was initially approved for use in the United States in 1982. It is available over the counter in pharmacies and from family planning centers, and it can be provided by your healthcare provider.

The Food and Drug Administration (FDA) approved the pill for unrestricted sale in 2013, so it can be sold in drugstores to people of any age or gender without a prescription or having to show any ID. It is sold in every state since it is not an abortion pill and will not terminate an existing pregnancy. Therefore, it is not connected to, nor affected by, the Supreme Court's 2022 Dobbs v. Jackson Women's Health Organization ruling, which effectively overturned Roe v. Wade.

"Most pharmacies carry Plan B or a generic option," said Cristin Hackel, B.S., R.N.C., a nurse practitioner at Nurx, a telehealth provider based in Bethesda, Maryland. She advised that you can buy it online to keep it available at home.

The pill has a shelf life of four years after it is manufactured. However, it stays in your body only for a short time, so if you take it the day before having unprotected sex, it may not work.

Some medications and supplements can alter the efficacy of Plan B, so let your doctor or pharmacist know about any drugs you are currently taking. Some common ones that can affect Plan B include:

• Barbiturates
• Bosentan
• Carbamazepine
• Felbamate
• Griseofulvin
• Oxcarbazepine
• Phenytoin
• Rifampin
• St. John's wort
• Topiramate
• Some HIV/AIDS medications

Are there instances in which Plan B is not the right choice?

There is conflicting evidence on whether a person's weight can affect the efficacy of Plan B. The manufacturer and the FDA say it is safe for people who weigh more than 165 pounds. However, women over that threshold may be advised or decide to take ella, another type of emergency contraception.

Hackel explained some pros and cons of ella:

• It can be taken five days after sex.
• It has an 85 percent effectiveness rate when taken correctly.
• It requires a prescription and cannot be purchased over the counter.
• It can interact with other birth control methods, making it less effective.
• It can be more expensive than Plan B.

"Both Plan B and ella need to be taken before ovulation occurs to be effective, but are not harmful if you don't know if you've ovulated," she said.

Side effects of Plan B

Like any drug, Plan B has potential side effects. Grover explained some common ones include the following:

• Nausea
• Vomiting
• Menstrual irregularities
• Dizziness
• Diarrhea
• Breast tenderness
• Tiredness

Even though no form of emergency contraception is considered dangerous, there are risks to taking it too often, since your body is exposed to more hormones than it would be under normal circumstances, or if you were on standard contraception options.

Grover said some existing side effects that Plan B can exacerbate if used too frequently include:

• Menstrual changes
• Headaches
• Abdominal pain

Ironically, Plan B could lead to pregnancy because it can disrupt your menstrual cycle, which can mean you ovulate at unexpected times. This can make it more challenging to track your periods and know when you are fertile. If your period is more than a week late after taking Plan B, you should take a pregnancy test.

Taking it too often can also suppress menstrual cycles and ovulatory cycles, Grover explained. This can make it more difficult to know when you are fertile when trying to conceive.

It is important to remember that Plan B does not protect against sexually transmitted infections (STIs) and diseases (STDs). Condoms, a barrier method of contraception, can also provide protection against STIs.

Plan B isn't the only option

"Longer-term birth control methods are significantly more effective at preventing pregnancy than routinely taking Plan B as your only method of birth control, and they are often cheaper," Grover said.

Longer-acting contraception options include:

• The birth control implant (Nexplanon)
• Intrauterine system (IUS)
• Intrauterine device (IUD or coil)
• Contraceptive injection

Shorter-term contraceptive options include:

• Combined pill
• Progestogen-only pill
• Vaginal ring
• Contraceptive patch

Not sure what contraception method will work best for your lifestyle? Speak to your doctor or family planning clinic. For those who don't plan to have children, there are permanent methods such as vasectomy or tubal ligation.

If you don't have a regular OB-GYN or other women's health specialist, telehealth might be a way to connect with one. Video visits have become a viable option for most people, and more physicians have added them as a service. Giddy telehealth makes it easy to get connected to a qualified healthcare professional who can help with a variety of conditions.