Comparative Pharmacology
Head-to-head clinical analysis: NORCEPT E 1 35 28 versus NORDETTE 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORCEPT E 1 35 28 versus NORDETTE 28.
NORCEPT-E 1/35 28 vs NORDETTE-28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen (ethinyl estradiol) and progestin (norethindrone) contraceptive: suppresses gonadotropin release, inhibits ovulation, thickens cervical mucus, and alters endometrial lining.
Combined estrogen-progestin oral contraceptive. Suppresses gonadotropin (FSH, LH) release from pituitary, inhibiting ovulation. Increases cervical mucus viscosity and alters endometrial lining.
1 tablet orally once daily for 21 days, followed by 7 days of placebo tablets.
One tablet orally once daily for 28 consecutive days.
None Documented
None Documented
Norethindrone: 5-14 hours; ethinyl estradiol: 13-27 hours. The terminal half-life of norethindrone is about 10 hours, allowing once-daily dosing; ethinyl estradiol's longer half-life contributes to steady-state concentrations within 3-5 days.
Ethinyl estradiol: 13-27 hours (mean 17 hours); Levonorgestrel: 11-45 hours (mean 24 hours); clinical context: steady-state reached after 5-7 days.
Renal (primarily as metabolites) and fecal; approximately 50-60% excreted in urine, 30-40% in feces. Ethinyl estradiol and norethindrone are extensively metabolized via hydroxylation and conjugation; glucuronide and sulfate conjugates are eliminated in urine and bile.
Renal: ~50% as metabolites, ~20% unchanged; Fecal: ~30% as metabolites; Biliary: minimal.
Category C
Category C
Combined Oral Contraceptive
Combined Oral Contraceptive