Comparative Pharmacology
Head-to-head clinical analysis: ORTHO NOVUM 1 50 21 versus ORTHO NOVUM 1 50 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO NOVUM 1 50 21 versus ORTHO NOVUM 1 50 28.
ORTHO-NOVUM 1/50 21 vs ORTHO-NOVUM 1/50 28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive consisting of mestranol (estrogen) and norethindrone (progestin). Mestranol is converted to ethinyl estradiol, which suppresses gonadotropin release (FSH, LH) from the pituitary, inhibiting ovulation. Norethindrone induces changes in cervical mucus (increasing viscosity) and endometrial lining, creating a hostile environment for sperm implantation.
Combination oral contraceptive; suppresses gonadotropin secretion (FSH, LH) via estrogen and progestin, inhibiting ovulation, increasing cervical mucus viscosity, and altering endometrial structure.
One tablet orally once daily for 21 days, followed by 7 tablet-free days. Each tablet contains 1 mg norethindrone and 50 mcg mestranol.
One tablet (1 mg norethindrone/50 mcg mestranol) orally once daily for 21 days, followed by 7 days of placebo tablets (inactive) for a 28-day cycle.
None Documented
None Documented
Norethindrone: biphasic terminal half-life 7-9 hours for parent compound, 8-11 hours for metabolites; clinical steady-state achieved after 5-7 days.
Norethindrone: 5-12 h (mean 8 h); Mestranol: 12-24 h (mean 18 h); steady-state reached within 5-7 days
Renal 50-60% as glucuronide and sulfate conjugates of norethindrone and mestranol/metabolites; fecal 20-30% via biliary elimination.
Renal: ~50-60% as metabolites; fecal: ~30-40% as metabolites; biliary: <10%
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive