Comparative Pharmacology
Head-to-head clinical analysis: LOESTRIN FE 1 20 versus NORDETTE 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LOESTRIN FE 1 20 versus NORDETTE 28.
LOESTRIN FE 1/20 vs NORDETTE-28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive consisting of ethinyl estradiol and norethindrone acetate. Inhibits gonadotropin secretion (FSH, LH) via negative feedback on the hypothalamic-pituitary-ovarian axis, suppressing ovulation. Increases cervical mucus viscosity and alters endometrial structure, impeding sperm penetration and implantation.
Combined estrogen-progestin oral contraceptive. Suppresses gonadotropin (FSH, LH) release from pituitary, inhibiting ovulation. Increases cervical mucus viscosity and alters endometrial lining.
One tablet (norethindrone acetate 1 mg and ethinyl estradiol 20 mcg) orally once daily for 21 consecutive days, followed by one ferrous fumarate tablet (75 mg) orally once daily for 7 days.
One tablet orally once daily for 28 consecutive days.
None Documented
None Documented
Norethindrone: 6-9 hours (terminal). Ethinyl estradiol: 13-27 hours (terminal, mean 16 hours). Steady-state reached within 5-7 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.
Norethindrone: 50-60% renal (as metabolites), 20-30% fecal. Ethinyl estradiol: 40-50% renal (as glucuronide conjugates), 30-40% fecal (as sulfate conjugates).
Renal: ~50% as metabolites, ~20% unchanged; Fecal: ~30% as metabolites; Biliary: minimal.
Category C
Category C
Combined Oral Contraceptive
Combined Oral Contraceptive