Comparative Pharmacology
Head-to-head clinical analysis: CYCLESSA versus NORTREL 1 35 21.
Head-to-head clinical analysis: CYCLESSA versus NORTREL 1 35 21.
CYCLESSA vs NORTREL 1/35-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
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 (0.15 mg desogestrel/0.02 mg ethinyl estradiol) orally once daily for 21 days, followed by 7 days of placebo.
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Desogestrel: 38±13 hours (terminal); ethinyl estradiol: 14±3 hours (terminal). Steady-state reached after 7-10 days.
Norethindrone: 5-14 hours; Ethinyl estradiol: 17-24 hours. Steady-state achieved after 10 days.
Urine (50-60% as metabolites, <10% unchanged); feces (30-40% as metabolites); enterohepatic circulation.
Renal 50-60% as metabolites, fecal 40-50% as conjugates, <1% unchanged
Category C
Category C
Oral Contraceptive
Oral Contraceptive