Comparative Pharmacology
Head-to-head clinical analysis: NORINYL 1 80 21 DAY versus NORQUEST FE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORINYL 1 80 21 DAY versus NORQUEST FE.
NORINYL 1+80 21-DAY vs NORQUEST FE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing norethindrone (a progestin) and ethinyl estradiol (an estrogen). Inhibits ovulation by suppressing gonadotropin release (FSH and LH). Also increases cervical mucus viscosity and alters endometrial morphology.
NORQUEST FE is a combination oral contraceptive containing ethinyl estradiol and norethindrone. Ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation. Norethindrone induces progestational changes in the endometrium, increasing cervical mucus viscosity, and also inhibits ovulation.
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
One tablet orally once daily, each tablet containing 1 mg norethindrone acetate and 20 mcg ethinyl estradiol (21 active tablets) followed by 7 ferrous fumarate tablets.
None Documented
None Documented
Norethindrone: 8-11 hours; Mestranol: 12-24 hours (metabolized to ethinyl estradiol with half-life 20-27 hours). Steady-state after 5-7 days.
Terminal half-life: 6-8 hours. Clinical context: Supports once-daily dosing with sustained therapeutic effect.
Renal (40-60% as metabolites), fecal (20-30%)
Renal: 80% (50% unchanged, 30% as metabolites); Fecal: 19%; Biliary: <1%
Category C
Category C
Oral Contraceptive
Oral Contraceptive