Comparative Pharmacology
Head-to-head clinical analysis: CYCLAFEM 7 7 7 versus CYCLESSA.
Head-to-head clinical analysis: CYCLAFEM 7 7 7 versus CYCLESSA.
CYCLAFEM 7/7/7 vs CYCLESSA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive. Ethinyl estradiol suppresses gonadotropin release (FSH, LH) via negative feedback on hypothalamic-pituitary axis; norethindrone induces endometrial changes that inhibit implantation and thickens cervical mucus.
Combination of estrogen (ethinyl estradiol) and progestin (desogestrel) inhibits ovulation by suppressing gonadotropin release, increases viscosity of cervical mucus to impede sperm penetration, and alters endometrial receptivity.
One tablet (norethindrone 0.5 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days, then one tablet (norethindrone 0.75 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days, then one tablet (norethindrone 1 mg/ethinyl estradiol 35 mcg) orally once daily for 7 days. Dispensed in a 21-tablet pack with 7 placebo tablets. For contraception, take one tablet daily at same time each day for 28 days; begin next pack after 28-day cycle.
One tablet (0.15 mg desogestrel/0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.
None Documented
None Documented
Terminal half-life: 5-13 hours (mean 8 hrs); clinical context: supports every-28-day dosing interval for intramuscular depot.
Desogestrel: 38±13 hours (terminal); ethinyl estradiol: 14±3 hours (terminal). Steady-state reached after 7-10 days.
Renal: ~50-60% as conjugated metabolites; Fecal: ~30-40% via bile; <1% unchanged.
Urine (50-60% as metabolites, <10% unchanged); feces (30-40% as metabolites); enterohepatic circulation.
Category C
Category C
Oral Contraceptive
Oral Contraceptive