Ulipristal acetate

Skeletal structure of Ulipristal Acetate

Ulipristal acetate is a medication used primarily for emergency contraception and the treatment of uterine fibroids. It is a selective progesterone receptor modulator (SPRM) that exhibits both agonistic and antagonistic effects on the progesterone receptor.

Mechanism of Action

Ulipristal acetate works by inhibiting or delaying ovulation. It binds to the progesterone receptor, altering the normal function of progesterone, which is crucial for ovulation and implantation. By modulating the receptor, ulipristal acetate prevents the release of an egg from the ovary and may also alter the endometrium, making it less suitable for implantation.

Uses

Emergency Contraception

Ulipristal acetate is used as an emergency contraceptive to prevent pregnancy after unprotected intercourse or contraceptive failure. It is effective when taken within 120 hours (5 days) after the event. It is marketed under the brand name Ella in the United States and EllaOne in Europe.

Treatment of Uterine Fibroids

In addition to its use in emergency contraception, ulipristal acetate is also used to treat moderate to severe symptoms of uterine fibroids in adult women of reproductive age. It helps reduce fibroid size and control bleeding.

Side Effects

Common side effects of ulipristal acetate include headache, nausea, abdominal pain, and menstrual irregularities. Some women may experience delayed menstruation or changes in their menstrual cycle after taking the medication.

Contraindications

Ulipristal acetate should not be used by women who are already pregnant or who have a known hypersensitivity to the drug. It is also contraindicated in women with severe liver impairment.

Related Pages

• Emergency contraception
• Uterine fibroid
• Progesterone receptor modulator