Comparative Pharmacology
Head-to-head clinical analysis: DEMULEN 1 35 21 versus ENOVID E 21.
Head-to-head clinical analysis: DEMULEN 1 35 21 versus ENOVID E 21.
DEMULEN 1/35-21 vs ENOVID-E 21
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.
Norethindrone is a progestin that suppresses gonadotropin release, inhibiting ovulation; mestranol is an estrogen that stabilizes endometrium and provides cycle control.
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 (norethynodrel 2.5 mg, mestranol 0.1 mg) orally once daily for 21 consecutive days, followed by 7 days without medication. Repeat cycle.
None Documented
None Documented
Ethinyl estradiol: 13±3 hours (terminal); norethindrone: 8±3 hours. Steady-state achieved after ~5 days.
Terminal elimination half-life: 27–36 hours (mean 30.8 h). Steady-state reached after 5–7 days. Clinical context: allows once-daily dosing with stable estrogenic effect.
Renal (primarily as glucuronide and sulfate conjugates): ~60%; fecal: ~40%
73% renal (45% as unchanged norethindrone, 20% as conjugates, 8% as other metabolites), 27% fecal via bile. Enterohepatic recirculation accounts for 15% of total clearance.
Category C
Category C
Oral Contraceptive
Oral Contraceptive