Comparative Pharmacology
Head-to-head clinical analysis: NORINYL 1 50 28 DAY versus NORINYL 1 80 21 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORINYL 1 50 28 DAY versus NORINYL 1 80 21 DAY.
NORINYL 1+50 28-DAY vs NORINYL 1+80 21-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Norethindrone and ethinyl estradiol combination works by suppressing gonadotropin-releasing hormone (GnRH) from the hypothalamus, reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, thereby inhibiting ovulation. Norethindrone also alters cervical mucus viscosity and endometrial lining, impeding sperm penetration and implantation.
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.
One tablet orally once daily for 28 days, with 7 inactive tablets during the last 7 days. Each active tablet contains norethindrone 1 mg and ethinyl estradiol 50 mcg.
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
None Documented
None Documented
Norethindrone: ~8-11 hours; Mestranol: 24 hours (prodrug, ethinyl estradiol half-life ~13-27 hours).
Norethindrone: 8-11 hours; Mestranol: 12-24 hours (metabolized to ethinyl estradiol with half-life 20-27 hours). Steady-state after 5-7 days.
Renal: ~40% as metabolites; Biliary/Fecal: ~60% as metabolites.
Renal (40-60% as metabolites), fecal (20-30%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive