Comparative Pharmacology
Head-to-head clinical analysis: DEMULEN 1 35 21 versus LO LARIN FE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DEMULEN 1 35 21 versus LO LARIN FE.
DEMULEN 1/35-21 vs LO LARIN FE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol (estrogen) and ethynodiol diacetate (progestin). Inhibits gonadotropin secretion (FSH, LH) via negative feedback on hypothalamic-pituitary axis, suppressing ovulation. Additionally, thickens cervical mucus and alters endometrial receptivity.
Combination of ethinyl estradiol (estrogen) and norethindrone (progestin) inhibits gonadotropin release, preventing ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial lining, reducing implantation likelihood.
One tablet orally once daily for 21 days, followed by 7 days off. Each tablet contains 1 mg ethynodiol diacetate and 35 mcg ethinyl estradiol.
One tablet orally once daily for 28 consecutive days. Each tablet contains norethindrone acetate 1 mg and ethinyl estradiol 20 mcg. Active tablets (21 days) followed by ferrous fumarate 75 mg inert tablets (7 days).
None Documented
None Documented
Ethinyl estradiol: 13±3 hours (terminal); norethindrone: 8±3 hours. Steady-state achieved after ~5 days.
Ethinyl estradiol: ~13-17 hours; norethindrone: ~8-12 hours; steady-state achieved within 5-7 days; clinical significance: missed doses may require backup contraception.
Renal (primarily as glucuronide and sulfate conjugates): ~60%; fecal: ~40%
Renal: 30-50% as ethinyl estradiol metabolites and norethindrone metabolites; fecal: 30-50% primarily as norethindrone metabolites; biliary excretion contributes to enterohepatic circulation.
Category C
Category C
Oral Contraceptive
Oral Contraceptive