Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 21 versus LESSINA 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 21 versus LESSINA 28.
LESSINA-21 vs LESSINA-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 a progestin (levonorgestrel) and an estrogen (ethinyl estradiol). Inhibits ovulation by suppressing gonadotropin release; increases cervical mucus viscosity to impede sperm penetration, and induces endometrial changes that reduce 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 (0.1 mg levonorgestrel and 0.02 mg ethinyl estradiol) orally once daily for 28 days, starting on the first day of menstrual cycle.
None Documented
None Documented
17-21 hours (terminal elimination half-life; clinical significance: allows once-daily dosing, but missed doses increase risk of ovulation)
Terminal elimination half-life: 18-22 hours; clinically relevant for once-daily dosing.
Renal (70% as unchanged drug and metabolites), fecal (30% as metabolites)
Renal: 30% as unchanged drug and metabolites; biliary/fecal: 70% as metabolites.
Category C
Category C
Oral Contraceptive
Oral Contraceptive