Comparative Pharmacology
Head-to-head clinical analysis: GENCEPT 10 11 28 versus NORINYL 1 80 21 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: GENCEPT 10 11 28 versus NORINYL 1 80 21 DAY.
GENCEPT 10/11-28 vs NORINYL 1+80 21-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination of ethinyl estradiol (estrogen) and levonorgestrel (progestin) inhibits ovulation by suppressing gonadotropin release, increases cervical mucus viscosity to impede sperm penetration, and alters endometrial receptivity.
Combination oral contraceptive containing norethindrone (a progestin) and ethinyl estradiol (an estrogen). Inhibits ovulation by suppressing gonadotropin release (FSH and LH). Also increases cervical mucus viscosity and alters endometrial morphology.
One tablet (ethinyl estradiol 0.01 mg/levonorgestrel 0.1 mg) orally once daily for 28 days. For the first 21 days, active tablets are taken; the next 7 days are placebo tablets.
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
None Documented
None Documented
Terminal elimination half-life is approximately 8-12 hours. Steady state is achieved within 2-3 days.
Norethindrone: 8-11 hours; Mestranol: 12-24 hours (metabolized to ethinyl estradiol with half-life 20-27 hours). Steady-state after 5-7 days.
Renal excretion accounts for approximately 70% of elimination (as unchanged drug and metabolites), with about 10% biliary/fecal. The remaining is metabolized.
Renal (40-60% as metabolites), fecal (20-30%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive