Comparative Pharmacology
Head-to-head clinical analysis: LEVORA 0 15 30 21 versus ORTHO NOVUM 7 14 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEVORA 0 15 30 21 versus ORTHO NOVUM 7 14 28.
LEVORA 0.15/30-21 vs ORTHO-NOVUM 7/14-28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive: ethinyl estradiol suppresses gonadotropin release via negative feedback on hypothalamic-pituitary axis; levonorgestrel inhibits ovulation and thickens cervical mucus, impairing sperm penetration. Also induces endometrial atrophy.
Combination oral contraceptive containing ethinyl estradiol and norethindrone. Suppresses gonadotropin release (FSH, LH) via negative feedback, inhibiting ovulation. Also increases cervical mucus viscosity and alters endometrial receptivity.
One tablet orally once daily for 21 days, followed by 7 tablet-free days.
One tablet daily for 28 days; each tablet contains norethindrone 0.5 mg and ethinyl estradiol 0.035 mg (days 1-7), norethindrone 0.75 mg and ethinyl estradiol 0.035 mg (days 8-14), norethindrone 1 mg and ethinyl estradiol 0.035 mg (days 15-21), and placebo (days 22-28). Take at same time each day.
None Documented
None Documented
20-30 hours for ethinyl estradiol; 2-4 hours for levonorgestrel. Steady-state reached in 5-7 days
Ethinyl estradiol: ~13-27 h (mean 17 h); Norethindrone: ~5-14 h (mean 8 h). Clinical context: steady-state achieved after ~5 days; half-life supports daily dosing.
Urine (50-60% as metabolites), feces (30-40% as glucuronides); <10% unchanged
Renal: ~50-60% (metabolites); biliary/fecal: ~30-40% (metabolites); unchanged drug <1% in urine.
Category C
Category C
Oral Contraceptive
Oral Contraceptive