Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 21 versus ORTHO NOVUM 7 7 7 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 21 versus ORTHO NOVUM 7 7 7 28.
LESSINA-21 vs ORTHO-NOVUM 7/7/7-28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol and levonorgestrel. Suppresses gonadotropin release (FSH, LH) from pituitary, inhibiting ovulation. Causes cervical mucus thickening and endometrial alterations, impeding sperm penetration and implantation.
Combination of estrogen (ethinyl estradiol) and progestin (norethindrone) inhibits gonadotropin secretion, preventing ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial development, reducing implantation likelihood.
One tablet (0.1 mg levonorgestrel, 0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days placebo or no tablets.
One tablet orally once daily for 28 consecutive days (21 active tablets followed by 7 placebo tablets). Each active tablet contains 0.035 mg ethinyl estradiol and varying progestin doses: 7 tablets of 0.5 mg norethindrone, 7 tablets of 0.75 mg norethindrone, and 7 tablets of 1 mg norethindrone.
None Documented
None Documented
17-21 hours (terminal elimination half-life; clinical significance: allows once-daily dosing, but missed doses increase risk of ovulation)
EE: terminal half-life 13-27 hours (mean ~17 hours); NET: 7-13 hours (mean ~10 hours). Clinical context: steady state reached after 4-7 days; missed pills may reduce contraceptive efficacy.
Renal (70% as unchanged drug and metabolites), fecal (30% as metabolites)
Ethinyl estradiol (EE) is excreted in urine (40%) and feces (60%) as glucuronide and sulfate conjugates. Norethindrone (NET) is excreted primarily in urine (60-80%) as glucuronide conjugates, with 10% in feces. Biliary excretion contributes minimally.
Category C
Category C
Oral Contraceptive
Oral Contraceptive