Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 21 versus LEVORA 0 15 30 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 21 versus LEVORA 0 15 30 21.
LESSINA-21 vs LEVORA 0.15/30-21
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 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.
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 21 days, followed by 7 tablet-free days.
None Documented
None Documented
17-21 hours (terminal elimination half-life; clinical significance: allows once-daily dosing, but missed doses increase risk of ovulation)
20-30 hours for ethinyl estradiol; 2-4 hours for levonorgestrel. Steady-state reached in 5-7 days
Renal (70% as unchanged drug and metabolites), fecal (30% as metabolites)
Urine (50-60% as metabolites), feces (30-40% as glucuronides); <10% unchanged
Category C
Category C
Oral Contraceptive
Oral Contraceptive