Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 21 versus OVRAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 21 versus OVRAL.
LESSINA-21 vs OVRAL
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.
OVRAL is a combination oral contraceptive containing ethinyl estradiol and norgestrel. It inhibits ovulation by suppressing gonadotropin-releasing hormone (GnRH) secretion from the hypothalamus, reducing follicle-stimulating hormone (FSH) and luteinizing hormone (LH) release from the pituitary. Additionally, it increases cervical mucus viscosity and alters endometrial receptivity, impeding sperm penetration and implantation.
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 (norgestrel 0.3 mg with ethinyl estradiol 0.03 mg) orally once daily for 21 days followed by 7 days of placebo.
None Documented
None Documented
17-21 hours (terminal elimination half-life; clinical significance: allows once-daily dosing, but missed doses increase risk of ovulation)
Norgestrel: 24–32 hours; Ethinyl estradiol: 12–18 hours; steady-state achieved after 5–7 days
Renal (70% as unchanged drug and metabolites), fecal (30% as metabolites)
Renal (60% as metabolites, ~40% unchanged); biliary/fecal (40%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive