Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 28 versus OGESTREL 0 5 50 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 28 versus OGESTREL 0 5 50 21.
LESSINA-28 vs OGESTREL 0.5/50-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Combination of norgestrel and ethinyl estradiol suppresses gonadotropin release, inhibiting ovulation; alters cervical mucus and endometrial lining.
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.
One tablet (norgestrel 0.5 mg / ethinyl estradiol 0.05 mg) orally once daily for 21 days, followed by 7 placebo days.
None Documented
None Documented
Terminal elimination half-life: 18-22 hours; clinically relevant for once-daily dosing.
Norgestrel: 24-32 hours; Ethinyl estradiol: 7-12 hours. Clinical context: Steady state achieved after 5-7 days.
Renal: 30% as unchanged drug and metabolites; biliary/fecal: 70% as metabolites.
Renal: ~50% (metabolites); Fecal/Biliary: ~50% (metabolites); <1% unchanged in urine.
Category C
Category C
Oral Contraceptive
Oral Contraceptive