Comparative Pharmacology
Head-to-head clinical analysis: HAILEY FE 1 5 30 versus NORLESTRIN 21 2 5 50.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HAILEY FE 1 5 30 versus NORLESTRIN 21 2 5 50.
HAILEY FE 1.5/30 vs NORLESTRIN 21 2.5/50
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive that suppresses gonadotropin release (FSH and LH) from the pituitary, inhibiting ovulation. Additionally, increases viscosity of cervical mucus and alters endometrial receptivity.
Combination oral contraceptive containing an estrogen (ethinyl estradiol) and a progestin (norethindrone acetate). Inhibits ovulation by suppressing gonadotropin release. Increases viscosity of cervical mucus, impeding sperm penetration, and alters endometrial receptivity.
One tablet orally once daily for 21 consecutive days, followed by 7 days of placebo tablets.
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Ethinyl estradiol: terminal half-life ~17-24 hours; norethindrone: terminal half-life ~5-14 hours (mean 11 hours). The clinical significance is that steady-state is reached within 5-7 days.
Norethindrone: 8 hours (terminal); Ethinyl estradiol: 13 hours (terminal). Clinical context: Steady-state achieved after 3-5 days; dosing interval based on once-daily administration.
Ethinyl estradiol is primarily excreted renally (40-45%) and via bile/feces (45-55%). Norethindrone is excreted 50-60% renally and 30-40% fecally.
Renal: 50-60% as metabolites (glucuronide and sulfate conjugates of norethindrone and ethinyl estradiol); fecal: 30-40% via biliary elimination; <1% unchanged.
Category C
Category C
Oral Contraceptive
Oral Contraceptive