Comparative Pharmacology
Head-to-head clinical analysis: ORTHO NOVUM 1 35 21 versus ORTHO NOVUM 1 50 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO NOVUM 1 35 21 versus ORTHO NOVUM 1 50 21.
ORTHO-NOVUM 1/35-21 vs ORTHO-NOVUM 1/50 21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive; suppresses gonadotropin (FSH and LH) secretion via negative feedback, inhibiting ovulation. Increases cervical mucus viscosity and alters endometrial lining, impairing sperm penetration and implantation.
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.
One tablet orally once daily for 21 days, followed by 7 placebo tablets. Each tablet contains 1 mg norethindrone and 0.035 mg ethinyl estradiol.
One tablet orally once daily for 21 days, followed by 7 tablet-free days. Each tablet contains 1 mg norethindrone and 50 mcg mestranol.
None Documented
None Documented
Norethindrone: 7-9 hours (terminal); Ethinyl estradiol: 13-27 hours (terminal). At steady state, clinical contraceptive efficacy is maintained with daily dosing.
Norethindrone: biphasic terminal half-life 7-9 hours for parent compound, 8-11 hours for metabolites; clinical steady-state achieved after 5-7 days.
Renal (approx. 40% as metabolites, <10% unchanged), fecal (approx. 60% as metabolites, primarily via bile).
Renal 50-60% as glucuronide and sulfate conjugates of norethindrone and mestranol/metabolites; fecal 20-30% via biliary elimination.
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive