Comparative Pharmacology
Head-to-head clinical analysis: CYCLAFEM 1 35 versus TRI SPRINTEC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYCLAFEM 1 35 versus TRI SPRINTEC.
CYCLAFEM 1/35 vs TRI-SPRINTEC
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 of ethinyl estradiol and norgestimate suppresses gonadotropin release, inhibiting ovulation, and increases viscosity of cervical mucus to inhibit sperm penetration.
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 (0.035 mg ethinyl estradiol / 0.250 mg norgestimate) orally once daily for 21 days, followed by 7 days of placebo tablets. Repeat cycle.
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.
Norelgestromin: 28 hours; Ethinyl estradiol: 17 hours. Steady-state achieved within 7 days.
Renal 40-60% as glucuronide and sulfate conjugates, biliary/fecal 20-40%.
Renal: 50% (metabolites); Fecal: 35% (eliminated in bile); unchanged drug <1%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive