Comparative Pharmacology
Head-to-head clinical analysis: JUNEL 1 20 versus NORINYL 1 80 21 DAY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: JUNEL 1 20 versus NORINYL 1 80 21 DAY.
JUNEL 1/20 vs NORINYL 1+80 21-DAY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive. Ethinyl estradiol is a synthetic estrogen that suppresses gonadotropin release by inhibiting hypothalamic GnRH secretion. Norethindrone acetate is a progestin that suppresses LH surge and thickens cervical mucus to inhibit sperm penetration and alters endometrial development.
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 (1 mg norethindrone acetate/20 mcg ethinyl estradiol) orally once daily for 21 days, followed by 7 placebo days, then repeat.
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
None Documented
None Documented
Ethinyl estradiol: 12-24 hours (terminal half-life). Norethindrone: 5-14 hours (terminal half-life). Achieves steady state within 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: 30-50% (metabolites as glucuronide and sulfate conjugates). Fecal: 20-40% (biliary elimination of metabolites). Unchanged drug: <5% renal.
Renal (40-60% as metabolites), fecal (20-30%)
Category C
Category C
Oral Contraceptive
Oral Contraceptive