Comparative Pharmacology
Head-to-head clinical analysis: LESSINA 21 versus OVULEN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LESSINA 21 versus OVULEN.
LESSINA-21 vs OVULEN
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.
Ovulen is a combination oral contraceptive containing ethynodiol diacetate (a progestin) and mestranol (an estrogen). It inhibits ovulation by suppressing gonadotropin-releasing hormone (GnRH) from the hypothalamus, reducing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion from the pituitary. It also increases cervical mucus viscosity and alters endometrial development, 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.
1 tablet (1 mg ethynodiol diacetate, 50 mcg mestranol) orally once daily for 21 days, followed by 7 days of placebo or no medication.
None Documented
None Documented
17-21 hours (terminal elimination half-life; clinical significance: allows once-daily dosing, but missed doses increase risk of ovulation)
Ethinylestradiol: 10-20 hours (mean 17 hours); Dimethisterone: 10-15 hours. Clinical context: Steady state achieved after 3-5 days; elimination prolonged in hepatic impairment.
Renal (70% as unchanged drug and metabolites), fecal (30% as metabolites)
Renal: 50-60% as metabolites (glucuronide and sulfate conjugates), biliary/fecal: 40-50% (enterohepatic circulation).
Category C
Category C
Oral Contraceptive
Oral Contraceptive