Plan B can prevent pregnancy up to 89% of the time when taken as prescribed.
As soon as possible following unprotected sexual activity, use Plan B. The sooner it is used, the more effective it will be.
Plan B is a secure and reliable method for preventing pregnancy following unprotected sexual activity.
Side Effects and Risks
Vomiting and nausea are two of Plan B's most frequent side effects. Additional negative effects include:
cramps or pain in the abdomen Breast sensitivity Diarrhea Dizziness Fatigue Headache Mood swings, including depression
Immediately get in touch with your doctor or other healthcare provider if you notice any of these side effects.
Sexually transmitted infections (STIs) are not covered by Plan B. To lower your risk of spreading STIs, use condoms.
Do not take Plan B if you are pregnant or suspect that you may be pregnant. Plan B won't end a pregnancy that has already started and is not an abortion.
Plan B is offered as a tablet with a single dose. One tablet (0.75 mg levonorgestrel) taken as soon as possible after unprotected intercourse is the recommended dosage.
Contact your doctor or other healthcare professional to discuss whether you need to repeat the dose if you vomit within two hours of taking Plan B.
You can take a second dose of Plan B (0.75 mg levonorgestrel) 12 hours after the first dose if you're not sure when you had unprotected intercourse or if you think you may have already ovulated. If it has been more than five days since unprotected sexual contact, this might not be necessary.
Drugs like:Plan B may interact with other drugs like:
Blood-thinning agents (anticoagulants) medication for epilepsy Protease inhibitors for HIV tranquilizers and sedatives
Before using Plan B, consult your doctor or other healthcare professional if you are currently taking any of these medications.
Birth control pills do not interact with Plan B. But if you vomit within two hours of taking Plan B, it might make birth control pills less effective. Use a backup method of contraception for at least the following week if this occurs.
Mechanism of Action
Plan B functions by postponing or preventing ovulation. Once the egg has been fertilized, it is ineffective.
Plan B can cut your risk of getting pregnant by up to 89% if you use it within 72 hours of unprotected sexual activity. The sooner it is used, the more effective it will be.
Plan B won't end a pregnancy that has already started and is not an abortion.
After being administered orally, Plan B is quickly absorbed. Levonorgestrel reaches its peak plasma concentrations in just two hours.
The body excretes levonorgestrel in the urine and feces, where it is widely distributed. Levonorgestrel has a half-life of about 12 hours.
Plan B is an emergency contraceptive pill (ECP) that contains only progestin and can be used to prevent pregnancy following unprotected sexual activity. Plan B functions by postponing or preventing ovulation. Once the egg has been fertilized, it is ineffective.
Women 17 years of age and older can purchase Plan B over-the-counter. Women 16 years of age and younger must have a prescription.
One tablet of Plan B, containing 0.75 mg of levonorgestrel, should be taken as soon as possible after unprotected sexual activity.