Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 28 versus LEVONEST.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 28 versus LEVONEST.
LESSINA-28 vs LEVONEST
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.
Levonorgestrel is a synthetic progestin that inhibits ovulation by suppressing luteinizing hormone (LH) surge, alters cervical mucus to impede sperm penetration, and induces endometrial changes that inhibit implantation.
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 (levonorgestrel 1.5 mg) orally as a single dose within 72 hours of unprotected intercourse.
None Documented
None Documented
Terminal elimination half-life: 18-22 hours; clinically relevant for once-daily dosing.
The terminal elimination half-life is approximately 24-30 hours. This relatively long half-life supports once-daily dosing and allows for stable plasma concentrations within 5-7 days of continuous use.
Renal: 30% as unchanged drug and metabolites; biliary/fecal: 70% as metabolites.
Renal excretion of conjugated metabolites accounts for approximately 60-80% of an administered dose; fecal elimination via bile accounts for 20-40%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive