Comparative Pharmacology
Head-to-head clinical analysis: MICROGESTIN 1 20 versus OVCON 35.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MICROGESTIN 1 20 versus OVCON 35.
MICROGESTIN 1/20 vs OVCON-35
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing estrogen (ethinyl estradiol) and progestin (norethindrone acetate). Inhibits gonadotropin secretion (FSH, LH) via negative feedback, preventing ovulation. Also causes cervical mucus thickening and endometrial thinning.
Combination estrogen-progestin contraceptive; suppresses gonadotropin release, inhibiting ovulation, and increases cervical mucus viscosity, impeding sperm penetration.
One tablet (norethindrone acetate 1 mg / ethinyl estradiol 20 mcg) orally once daily for 21 consecutive days, followed by 7 days of placebo or no tablets.
One tablet (35 mcg ethinyl estradiol and 0.4 mg norethindrone) orally once daily.
None Documented
None Documented
Norethindrone: 5.2-12.8 hours (mean ~8 hours); Ethinyl estradiol: 7-20 hours (mean ~13 hours); hepatic impairment prolongs.
Ethinyl estradiol: 5-18 hours (mean ~12 hours, biphasic); norethindrone: 5-14 hours (mean ~8 hours). Terminal half-life relevant for once-daily dosing.
Renal: 40% as metabolites, 20% as glucuronide and sulfate conjugates; Fecal: 35%; Biliary: <5%.
Renal 60% (metabolites, glucuronide conjugates), fecal 10%, biliary 5%, remainder via other pathways.
Category C
Category C
Oral Contraceptive
Oral Contraceptive