Comparative Pharmacology
Head-to-head clinical analysis: NORINYL 1 80 21 DAY versus PHILITH.
Peer-Reviewed Evidence
Head-to-head clinical analysis: NORINYL 1 80 21 DAY versus PHILITH.
NORINYL 1+80 21-DAY vs PHILITH
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing norethindrone (a progestin) and ethinyl estradiol (an estrogen). Inhibits ovulation by suppressing gonadotropin release (FSH and LH). Also increases cervical mucus viscosity and alters endometrial morphology.
PHILITH is a combined oral contraceptive containing ethinyl estradiol and drospirenone. Ethinyl estradiol suppresses gonadotropin release, while drospirenone is a progestin with antiandrogenic and antimineralocorticoid activity, inhibiting ovulation and altering cervical mucus.
One tablet orally once daily for 21 days, followed by 7 days of no active treatment.
1 mg orally once daily
None Documented
None Documented
Norethindrone: 8-11 hours; Mestranol: 12-24 hours (metabolized to ethinyl estradiol with half-life 20-27 hours). Steady-state after 5-7 days.
Terminal half-life 12 hours; clinically relevant for twice-daily dosing with steady state reached after 2-3 days.
Renal (40-60% as metabolites), fecal (20-30%)
Renal: 90% unchanged; biliary/fecal: 10% as metabolites.
Category C
Category C
Oral Contraceptive
Oral Contraceptive