Generic name: levonorgestrel emergency contraceptive [ LEE-voe-nor-jes-trel ]
Brand names: AfterPill, BionaFem, EContra EZ, Fallback Solo, Morning After, ... show all 12 brands My Choice, My Way, New Day, Opcicon One-Step, Plan B One-Step, React, Take Action
Drug class: Contraceptives
What is React?
React is used to prevent pregnancy after unprotected sex or failure of other forms of birth control (such as condom breakage, or missing 2 or more birth control pills).
React may also be used for purposes not listed in this medication guide.
React will not terminate pregnancy if the fertilized egg has already attached to the uterus.
Ask a doctor or pharmacist before taking levonorgestrel if you regularly use medication for seizures, tuberculosis, or HIV/AIDS. Certain other medicines can make levonorgestrel less effective.
Before taking this medicine
React is not intended for use as a routine form of birth control. Talk with your doctor about the many forms of birth control available.
Do not use this medicine if you are already pregnant. React will not terminate a pregnancy that has already begun (the fertilized egg has attached to the uterus).
Not approved for use by anyone younger than 17 years old.
You should not use levonorgestrel if you are allergic to it.
Ask a doctor or pharmacist before taking levonorgestrel if you regularly use medication for seizures, tuberculosis, or HIV/AIDS. Certain medications can make levonorgestrel less effective as an emergency form of contraception.
Levonorgestrel may slow breast milk production. Tell your doctor if you are breastfeeding.
How should I take React?
Use exactly as directed on the label, or as prescribed by your doctor.
React must be taken as soon as possible after unprotected sex (no later than 72 hours afterward).
Call your doctor right away if you vomit within 2 hours after taking React. Do not take a second dose without first asking your doctor.
If your period is late by 1 week or longer after the expected date, you may be pregnant. Get a pregnancy test and contact your doctor if you are pregnant. React will not terminate pregnancy if the fertilized egg has attached to the uterus.
Within 3 weeks after taking React, a doctor should confirm that you are not pregnant, and that this medicine has not caused any harmful effects.
Store at room temperature away from moisture and heat.
What happens if I miss a dose?
Since React is used as a single dose, it does not have a daily dosing schedule.
What happens if I overdose?
Because React is supplied as a single tablet in an exact strength, an overdose is unlikely to occur when the levonorgestrel is used as directed. Do not take more than one tablet at the same time.
What should I avoid while taking React?
React will not protect you from sexually transmitted diseases--including HIV and AIDS. Using a condom is the only way to protect yourself from these diseases. Avoid having unprotected sex.
React side effects
Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.
Call your doctor or seek emergency medical help if you have severe pain in your lower stomach or side. This could be a sign of a tubal pregnancy (a pregnancy that implants in the fallopian tube instead of the uterus). A tubal pregnancy is a medical emergency.
Common side effects of React may include:
breast pain or tenderness;
feeling tired; or
changes in your menstrual periods.
This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
What other drugs will affect React?
Certain other medications can make React less effective, which may result in pregnancy. Ask a doctor or pharmacist if React is safe to use if you are using any of the following medications:
seizure medication--carbamazepine, felbamate, fosphenytoin, phenobarbital, phenytoin, primidone.
This list is not complete. Other drugs may affect levonorgestrel, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.
Yes, Plan B (levonorgestrel) may lead to a delayed period or induce bleeding outside the typical menstrual cycle, as it contains a synthetic hormone. In order to prevent pregnancy, Plan B, similar to other contraceptive pills, needs to modify your hormonal levels, which can result in these menstrual alterations. It's worth noting that Plan B is linked to a higher likelihood of menstrual changes compared to regular birth control pills, due to its increased dosage. Continue reading
Yes. After taking the emergency contraceptive Plan B (levonorgestrel), it is considered safe to drink alcohol, and alcohol is not known to alter the efficacy of Plan B. While consuming alcohol after Plan B is not considered dangerous, some of the potential side effects of Plan B may be worsened by alcohol. Continue reading
Plan B (levonorgestrel) is estimated to be 60% to 94% effective at preventing pregnancy when taken within 3 days (72 hours) after unprotected sex. Somewhere between 0.6% to 2.6% of women who take Plan B within this time frame will still become pregnant. Continue reading
You can take Plan B (levonorgestrel) as many times as needed for emergency contraception. There is no known limit on the number of times you can safely use Plan B. Plan B can even be taken more than once in the same menstrual cycle. Continue reading
More about React (levonorgestrel)
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- Drug class: contraceptives
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Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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