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What Is Ulipristal Acetate?

Jacquelyn Gilchrist
Jacquelyn Gilchrist

Ulipristal acetate is a medication prescribed for emergency contraception. A doctor will not prescribe it as a birth control pill to be taken on a regular basis, but rather it is intended to prevent pregnancy in the event of unprotected sex or if a regular birth control method fails. This drug is also not intended to abort an already existing pregnancy. Patients should carefully follow their doctor's dosage instructions and be aware of the possible side effects before using ulipristal acetate.

This emergency contraceptive works by using the hormone progestin to prevent ovulation. Specifically, ulipristal acetate is classified as a selective progesterone receptor modulator. It reduces the chances of fertilization and implantation by altering the cervical mucus and the lining of the womb. This makes it less likely that sperm will fertilize an egg, as well as prevent a fertilized egg from attaching to the womb.

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Ulipristal acetate should be taken within 120 hours, or five days, following unprotected sex or the failure of another birth control method, such as a broken condom. The sooner a woman takes the drug, the more effective it is likely to be. One tablet equals one dosage and it may be taken with or without food. Those who vomit within three hours of taking a dose should contact their doctors, because the tablet may need to be taken again.

Women who use ulipristal acetate to prevent pregnancy must immediately resume taking their regular birth control. Doctors also recommend using a barrier method of birth control for the rest of that menstrual cycle. Some women may notice that their menstrual cycle becomes irregular following a dosage.

Some side effects may occur after taking ulipristal acetate, which should be reported to the doctor if they become severe. Patients may notice painful menstruation, nausea, and abdominal pain, which may become severe three to five weeks following a dose. Dizziness, headaches, and fatigue may also occur. Sometimes, changes in mood, breast tenderness, or pelvic, back, or muscle pain may result. Ulipristal acetate may very rarely cause painful intercourse, genital itching, and kidney problems.

Before taking this emergency contraceptive, patients must inform their doctors of their medical conditions, as well as any other medications or supplements they are taking. This drug is not intended for use during pregnancy and it is unknown if it may cause harm to a breastfeeding infant. Women should inform their doctors if they have a history of unexplained vaginal bleeding. Ulipristal acetate may interact with other medications and supplements, including St. John's wort, phenobarbital, and topiramate.

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