Comparative Pharmacology
Head-to-head clinical analysis: CYCLAFEM 1 35 versus HAILEY FE 1 5 30.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYCLAFEM 1 35 versus HAILEY FE 1 5 30.
CYCLAFEM 1/35 vs HAILEY FE 1.5/30
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol and norethindrone. Suppresses gonadotropin (FSH, LH) secretion via estrogen and progestin negative feedback, inhibiting ovulation. Progestin alters cervical mucus (sperm penetration) and endometrial receptivity.
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.
One tablet orally once daily. Each tablet contains 1 mg norethindrone and 0.035 mg ethinyl estradiol. Administer daily for 21 days followed by 7 days of placebo or no tablet.
One tablet orally once daily for 21 consecutive days, followed by 7 days of placebo tablets.
None Documented
None Documented
Half-life of norethindrone is 5-14 hours; ethinyl estradiol is 10-20 hours. Steady state reached after 5-7 days.
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.
Renal 40-60% as glucuronide and sulfate conjugates, biliary/fecal 20-40%.
Ethinyl estradiol is primarily excreted renally (40-45%) and via bile/feces (45-55%). Norethindrone is excreted 50-60% renally and 30-40% fecally.
Category C
Category C
Oral Contraceptive
Oral Contraceptive