Comparative Pharmacology
Head-to-head clinical analysis: BREVICON 28 DAY versus NORINYL 1 80 21 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BREVICON 28 DAY versus NORINYL 1 80 21 DAY.
BREVICON 28-DAY vs NORINYL 1+80 21-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive; ethinyl estradiol and norethindrone suppress gonadotropin secretion (FSH and LH) via negative feedback, inhibiting ovulation. Additionally, alters cervical mucus consistency and endometrial lining to impede 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 (0.5 mg norethindrone and 35 mcg ethinyl estradiol) orally once daily for 28 days (21 active tablets followed by 7 inert tablets).
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
None Documented
None Documented
Norethindrone: 8-11 hours; Ethinyl estradiol: 13-27 hours; half-life for ethinyl estradiol allows once-daily dosing
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 and unchanged drug; fecal/biliary: ~60% as metabolites
Renal (40-60% as metabolites), fecal (20-30%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive