Comparative Pharmacology
Head-to-head clinical analysis: ENOVID E versus ZOVIA 1 35E 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ENOVID E versus ZOVIA 1 35E 21.
ENOVID-E vs ZOVIA 1/35E-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination estrogen-progestin contraceptive. Suppresses gonadotropin release, inhibits ovulation, increases cervical mucus viscosity, and alters endometrial morphology.
Combination estrogen-progestin contraceptive; suppresses gonadotropin release, inhibits ovulation, alters cervical mucus and endometrial lining.
5 mg orally once daily for 20 days starting on day 5 of menstrual cycle
One tablet orally once daily at the same time each day for 21 days, followed by 7 placebo tablets (if included in the pack) or a 7-day pill-free interval. Each tablet contains ethinyl estradiol 0.035 mg and norethindrone 1 mg.
None Documented
None Documented
Norethynodrel: 5-10 hours; mestranol: 2-5 hours (metabolized to ethinyl estradiol, half-life 10-20 hours). Steady-state reached in 5-7 days.
Norethindrone: 5-12 hours (terminal elimination half-life, approximately 8 hours). Ethinyl estradiol: biphasic with terminal half-life of 10-20 hours (mean 15 hours). Clinical context: Steady state reached in 5-7 days.
Renal (50-60% as metabolites, <1% unchanged); fecal (40-50%)
Renal (approximately 40% as parent drug and metabolites; 20-40% as metabolites; 15-20% as unchanged drug), fecal (30-50% via bile as metabolites), and less than 2% in breast milk.
Category C
Category C
Oral Contraceptive
Oral Contraceptive