Mifepristone (RU-486)(miff eh prist’ own)
Korlym, Mifeprex
PREGNANCY CATEGORY X
Drug class
Abortifacient
Therapeutic Actions
Acts as an antagonist of progesterone sites in the endometrium, allowing prostaglandins to stimulate uterine contractions, causing implanted trophoblast to separate from the placental wall; may also decrease placental viability and accelerate degenerative changes resulting in sloughing of the endometrium.
Indications
Termination of pregnancy through 49 days gestational age; most effective when combined with a prostaglandin (Mifeprix)
Control of hyperglycemia secondary to hypercortisolism in adults with endogenous Cushing syndrome who have type 2 diabetes or glucose intolerance and have failed or are not candidates for surgery (Korlym)
Unlabeled uses: Postcoital contraception, endometriosis, unresectable meningioma, fetal death, or nonviable early pregnancy
Contraindications and Cautions
Contraindicated with allergy to prostaglandin preparations; acute PID; active cardiac, hepatic, pulmonary, renal disease; undiagnosed adrenal mass; hemorrhagic disorder, anticoagulation; ectopic pregnancy; and in patients with an IUD in place.
Use cautiously with history of asthma; anemia, jaundice, diabetes, epilepsy, scarred uterus, cervicitis, infected endocervical lesions, acute vaginitis, QT prolongation.
Available Forms
Tablets—200, 300 mg
Dosages
Adults
Termination of pregnancy: Day 1: 600 mg (3 tablets) PO taken as a single dose. Day 3: If termination of pregnancy cannot be confirmed, 400 mcg (2 tablets) misoprostol
(Cytotec). Day 14: Evaluation for termination of pregnancy; if unsuccessful, surgical intervention is suggested at this time. (Mifeprex)
Control of hyperglycemia with Cushing syndrome: 300 mg/day PO with a meal; may be titrated to a maximum 1,200 mg/day. (Korlym)
Patients with renal or hepatic impairment
Maximum dose, 600 mg/day PO.
