Comparative Pharmacology
Head-to-head clinical analysis: NORLESTRIN 28 1 50 versus NORTREL 1 35 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORLESTRIN 28 1 50 versus NORTREL 1 35 21.
NORLESTRIN 28 1/50 vs NORTREL 1/35-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin oral contraceptive; suppresses gonadotropin release via negative feedback on pituitary, inhibits ovulation, thickens cervical mucus, alters endometrial receptivity.
Combination of ethinyl estradiol (estrogen) and norethindrone (progestin) suppresses gonadotropin (FSH and LH) release from the pituitary, inhibiting ovulation, altering cervical mucus to impede sperm penetration, and inducing endometrial changes that reduce implantation likelihood.
One tablet orally once daily, each containing norethindrone 1 mg and ethinyl estradiol 50 mcg.
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Norethindrone: 8 hours; ethinyl estradiol: 12-15 hours; steady state achieved within 5-10 days.
Norethindrone: 5-14 hours; Ethinyl estradiol: 17-24 hours. Steady-state achieved after 10 days.
Norethindrone: 40% renal, 60% fecal; ethinyl estradiol: 40% renal, 60% fecal.
Renal 50-60% as metabolites, fecal 40-50% as conjugates, <1% unchanged
Category C
Category C
Oral Contraceptive
Oral Contraceptive