Adult: To control hyperglycaemia in patients w/ type 2 DM or glucose intolerance: Initially, 300 mg once daily, may increase in increments of 300 mg at 2-4 wk intervals. Max: 1.2 g once daily (but not more than 20 mg/kg daily). Patients taking strong CYP3A4 inhibitors: Max: 300 mg daily.
Oral Termination of pregnancy (49 days or less duration)
Adult: 600 mg as a single dose, followed by a prostaglandin (either misoprostol 400 mcg orally or gemeprost 1 mg vaginally) 36-48 hr later. Alternatively, 200 mg as a single dose, followed by gemeprost 1 mg vaginally 36-48 hr later.
Oral Softening and dilatation of cervix prior to surgical termination of pregnancy
Adult: 200 mg as a single dose given 36-48 hr prior to the procedure.
Oral Termination of pregnancy between 13-24 wk of gestation
Adult: As adjunct to prostaglandin: 600 mg as a single dose given 36-48 hr prior to prostaglandin therapy.
Oral Induction of labour following intrauterine fetal death
Adult: 600 mg daily for 2 consecutive days.
Oral Termination of pregnancy up to 63 days
Adult: 600 mg as a single dose followed by 1 mg gemeprost vaginally 36-48 hr later.
Termination of pregnancy: Monitor Hb, haematocrit and RBC count in cases of heavy bleeding; CBC in patients who show signs of infection. Conduct clinical exam and/or ultrasound to confirm complete termination of pregnancy. Cushing’s syndrome: Monitor thyroid function, serum glucose, psychiatric symptoms, signs/symptoms of adrenal insufficiency; cushingoid appearance.
Increased serum levels w/ CYP3A4 inhibitors (e.g. ketoconazole, itraconazole, erythromycin). Decreased serum levels w/ CYP3A4 inducers (e.g. dexamethasone, rifampicin, phenytoin). Potentially Fatal: Increased risk of adverse effects w/ simvastatin, lovastatin and CYP3A4 substrates w/ narrow therapeutic range (e.g. ciclosporin, pimozide, ergotamine). Antagonises the effect of glucocorticoids. Increased risk of vag bleeding w/ anticoagulants.
Description: Mifepristone is a synthetic steroid which blocks the effects of progesterone by competitively binding to the intracellular progesterone receptor. It sensitises the myometrium to the contraction-inducing action of prostaglandin. At higher doses, it blocks the effect of cortisol at the glucocorticoid receptor while increasing circulating cortisol concentrations. Pharmacokinetics: Absorption: Rapidly absorbed. Bioavailability: Approx 70%. Time to peak plasma concentration: Approx 1-2 hr. Distribution: Enters breast milk. Plasma protein binding: Approx 98%, mainly to α1-acid glycoprotein. Metabolism: Undergoes hepatic oxidative metabolism by CYP3A4 isoenzyme. Excretion: Via faeces (as metabolites) and urine (small amounts). Elimination half-life: Approx 18 hr.
G03XB01 - mifepristone ; Belongs to the class of antiprogestogens.
Anon. Mifepristone. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 20/01/2016.Buckingham R (ed). Mifepristone. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 20/01/2016.Korlym Tablet (Corcept Therapeutics Inc). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 20/01/2016.McEvoy GK, Snow EK, Miller J et al (eds). Mifepristone. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 20/01/2016.