Comparative Pharmacology
Head-to-head clinical analysis: GENCEPT 10 11 21 versus NORINYL 1 80 21 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: GENCEPT 10 11 21 versus NORINYL 1 80 21 DAY.
GENCEPT 10/11-21 vs NORINYL 1+80 21-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
GENCEPT 10/11-21 is a combination contraceptive vaginal ring containing ethinyl estradiol and etonogestrel. Ethinyl estradiol is an estrogen that suppresses gonadotropin release, inhibiting ovulation. Etonogestrel is a progestin that thickens cervical mucus, inhibiting sperm penetration, and alters the endometrium.
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 (10 mg ethinyl estradiol and 11 mg gestodene on days 1-7, then placebo on days 8-21) orally once daily for 21 days, followed by 7 placebo days.
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 24-30 hours; allows once-daily dosing; steady-state achieved in 5-7 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 (30-40% as unchanged drug and metabolites), biliary/fecal (50-60% as metabolites)
Renal (40-60% as metabolites), fecal (20-30%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive