Comparative Pharmacology
Head-to-head clinical analysis: CYCLAFEM 1 35 versus ENPRESSE 28.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYCLAFEM 1 35 versus ENPRESSE 28.
CYCLAFEM 1/35 vs ENPRESSE-28
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.
ENPRESSE-28 is a combined hormonal contraceptive containing ethinyl estradiol and desogestrel. It acts by suppressing gonadotropin release (FSH and LH) from the pituitary, inhibiting ovulation, thickening cervical mucus to impede sperm penetration, and altering the endometrium.
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.
1 tablet (ethinyl estradiol 0.035 mg / norgestimate 0.25 mg) orally once daily for 21 days, followed by 7 placebo days.
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.
Terminal elimination half-life is 18-24 hours, allowing once-daily dosing; steady-state achieved within 5-7 days.
Renal 40-60% as glucuronide and sulfate conjugates, biliary/fecal 20-40%.
Primarily renal excretion as unchanged drug (70-80%) and glucuronide conjugate (15-20%); biliary/fecal elimination accounts for <5%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive