Yes, Plan B can make you sick. Nausea and vomiting are among the most common side effects of emergency contraception. Most people who take it will not vomit, but many will feel nauseous for a day or two. This is a well-documented reaction to the high dose of synthetic progesterone in the pill, not a sign that something is wrong or that the pill is not working.
Why Does Plan B Cause Nausea?
Plan B contains levonorgestrel, a synthetic hormone. The dose in a single Plan B pill is much higher than the dose in a daily birth control pill. That sudden surge of hormone is what triggers nausea in many people.
The stomach is sensitive to hormonal shifts. This is the same reason morning sickness happens during early pregnancy. Your body reads the hormone change and responds with queasiness. It is a physical reaction, not a psychological one.
This side effect is common enough that it is listed on the package insert. Clinical trials and decades of real-world use confirm it. Most people feel the nausea peak within a few hours of taking the pill, and it usually fades within 24 hours.
How Common Are Plan B Side Effects?
Nausea is the most frequently reported side effect. Some research suggests roughly one in five people experience it. Vomiting is less common but still happens to some people.
Other common side effects include:
- Lower abdominal pain or cramping
- Headache
- Dizziness
- Fatigue
- Breast tenderness
- Irregular bleeding or spotting
These symptoms are temporary. They are the result of the hormone surge and typically resolve within a few days. If you are still feeling sick after three days, that is outside the typical window and worth a call to a clinician.
Does Vomiting Mean Plan B Did Not Work?
This is a real concern and the answer depends on timing. Vomiting can reduce the effectiveness of the pill, but only if the pill comes back up.
If you vomit within two hours of taking Plan B, the pill may not have been fully absorbed. The standard guidance is to contact a clinician or pharmacist. They may recommend taking another dose. If vomiting happens after two hours, the medication has likely been absorbed and you do not need a repeat dose.
This two-hour window is the standard clinical recommendation. It is based on how quickly the body absorbs levonorgestrel. The full dose is usually absorbed within that time frame.
Can You Prevent the Nausea?
You cannot eliminate the risk, but you can reduce it. Taking Plan B with food is the most practical step. A meal or a substantial snack slows digestion and can soften the hormone spike.
Some clinicians recommend an over-the-counter anti-nausea medication like dimenhydrinate (Dramamine) taken about an hour before Plan B. This is a common practice, but it is not an official protocol. No large clinical trials have specifically tested this combination for emergency contraception.
Eating a light meal is safe and may help. Taking anti-nausea medication is reasonable, but talk to a pharmacist first if you have other medical conditions or take other medications.
Is There a Difference Between Plan B and Other Emergency Contraception?
There are two main types of emergency contraception pills. Plan B is the levonorgestrel type. The other type contains ulipristal acetate, sold under the brand name ella.
Ulipristal acetate also causes nausea, but the rates may differ slightly. Some studies suggest the side effect profile is similar. Both types work by delaying ovulation, and both can make you feel sick.
The copper IUD is another emergency contraception option. It does not contain hormones, so it does not cause hormonal nausea. It is the most effective form of emergency contraception, but it requires a clinician to insert it within five days of unprotected sex.
If you have vomited with hormonal birth control before, you may prefer to discuss the copper IUD option with a clinician. It is a different mechanism entirely and avoids the hormone-related stomach upset.
When Should You Worry About Symptoms?
Most Plan B side effects are uncomfortable but harmless. There are a few signs that warrant medical attention.
If you vomit repeatedly for more than 24 hours, that is not a typical Plan B reaction. Contact a clinician. If you have severe abdominal pain that does not ease, seek care. Severe pain can be a sign of an ectopic pregnancy, which is a medical emergency.
Plan B is not an abortion pill. It does not end an existing pregnancy. It works by delaying ovulation so sperm cannot meet an egg. If you are already pregnant, Plan B will not work and will not harm the pregnancy.
If your next period is more than seven days late, take a pregnancy test. Plan B is highly effective but not 100 percent effective. A late period after taking Plan B requires confirmation that you are not pregnant.
Does Plan B Affect Future Fertility?
No. There is no evidence that emergency contraception affects long-term fertility. The hormone surge is temporary and clears from your body within days.
This question comes up often, and the answer is consistent across research and clinical guidelines. Taking Plan B once or even multiple times in a year does not change your ability to get pregnant later. It does not damage eggs, the uterus, or the hormonal system that controls your cycle.
Some people feel their next period is irregular after taking Plan B. That is common. The timing may shift by a few days, or bleeding may be lighter or heavier than usual. This is a temporary disruption, not a sign of permanent change.
What Should You Do If Plan B Makes You Vomit?
If you vomit within two hours of taking the pill, call a pharmacist or clinician. They will tell you whether to take another dose. Do not take a second dose on your own without checking, because doubling the hormone dose will increase nausea significantly.
If you vomit after two hours, the pill has been absorbed. You do not need another dose. The nausea and vomiting should subside as your body processes the hormone.
Stay hydrated. Sip water or an electrolyte drink. Eat bland foods like crackers or toast when you feel ready. Rest if you can. These steps will not stop the nausea, but they will help you manage it while it lasts.
Are There Alternatives to Plan B?
Yes. The levonorgestrel pill is one option, but not the only one.
Ella (ulipristal acetate) is a prescription emergency contraceptive. It is effective up to five days after unprotected sex. Some research suggests it works better than levonorgestrel, especially later in the five-day window. It also causes nausea, and the prescription requirement means you need to see a clinician to get it.
The copper IUD is the most effective emergency contraception. It is more than 99 percent effective and works for five days after unprotected sex. It also provides ongoing contraception for up to 12 years. It does not cause hormonal nausea because it contains no hormones.
The hormonal IUD is not approved for emergency contraception. Only the copper IUD has this indication.
Frequently Asked Questions
How long does Plan B nausea last?
Nausea typically lasts less than 24 hours. Most people feel the worst within the first few hours after taking the pill, and symptoms fade as the hormone level drops.
Can I take Plan B on an empty stomach?
You can, but taking it with food may reduce nausea. A light meal or snack before the pill can soften the hormone spike and lessen stomach upset.
Does Plan B make you throw up?
Some people do vomit, but most do not. Vomiting is a less common side effect than nausea, affecting roughly one in ten to one in twenty users.
What happens if I throw up after taking Plan B?
If you vomit within two hours, contact a pharmacist about a repeat dose. If vomiting happens after two hours, the pill is absorbed and no repeat dose is needed.
