Which of the following is glucocorticoid receptor blocker?
Ans. b (Mifepristone) (Ref. KDT 6th/310).# Mifepristone is orally active glucocorticoid receptor blocker (antiglucocorticoid activity), antiandrogenic as well as potent competitive anti-progesterone drug. QMIFEPRISTONE (RU 486)# It is a steroid with an affinity for progesterone receptors.# Single dose 600 mg or 25 mg bd for 4 days if ammenorrhea is of > 48 hours.# It does not prevent fertilization, but by blocking action of progesterone on endometrium, causing sloughing and shedding of deciduas and brings about abortion. However, emptying is incomplete and surgical evacuation is needed.# Adding PG (Misoprostol) on last day improves the rate of complete abortion.# Metabolized by CYP 3A4 (interacts with inhibitors-erythromycin, ketoconazole & inducers-RMP & anticonvulsants).Uses of Mifepristone:1. Termination of pregnancy# Used upto 7 week only as single dose of 600 mg (induces abortion in 60-85% cases).# Causes slowing of follicular development and delay s/failure of ovulation. Prevents secretory changes normally brought about by progesterone. It stimulates uterine contractions. Blocks decidualization. Causes 2deg leuteolysis.# Anorexia, nausea, tiredness, abdominal discomfort, uterine cramps, loose stools.02. Cervical ripening3. Postcoital contraception0# Given within 72 hrs of intercourse, Interferes with implantation, Highly effective4. Once a month contraceptive5. Induction of labour0# By blocking relaxant action of progesterone on uterus of late pregnancy.# May be tried in IUD and to deliver abnormal fetuses.6. Cushing syndrome (Large doses; Palliative effect)7. Under evaluation for Rx of:# Endometriosis# Uterine fibroid# Breast ca# Meningioma
Aminoglutethemide
Mifepristone
Trilostane
Ketoconazole
Endocrinology