Comparative Pharmacology
Head-to-head clinical analysis: MICROGESTIN 1 5 30 versus YAZ.
Peer-Reviewed Evidence
Head-to-head clinical analysis: MICROGESTIN 1 5 30 versus YAZ.
MICROGESTIN 1.5/30 vs YAZ
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing norethindrone acetate (progestin) and ethinyl estradiol (estrogen). Suppresses gonadotropin secretion (FSH, LH) via negative feedback on hypothalamic-pituitary axis, preventing ovulation. Also increases cervical mucus viscosity and alters endometrial receptivity.
Combination of ethinyl estradiol and drospirenone; suppresses gonadotropins (FSH and LH) inhibiting ovulation, and increases cervical mucus viscosity to impede sperm penetration. Drospirenone has antimineralocorticoid and antiandrogenic activity.
One tablet (norethindrone acetate 1.5 mg/ethinyl estradiol 30 mcg) orally once daily at the same time each day for 21 consecutive days, followed by 7 days of placebo tablets.
One tablet (0.02 mg ethinyl estradiol and 3 mg drospirenone) orally once daily for 24 days, followed by 2 days of placebo.
None Documented
None Documented
Norethindrone: 8-11 hours; Ethinyl estradiol: 13-19 hours. Steady-state reached within 5-7 days.
Terminal elimination half-life of drospirenone is 31.2-32.5 hours; ethinyl estradiol: 13-27 hours. Steady-state achieved after 10 days of daily dosing. Clinically, once-daily dosing maintains stable concentrations.
Renal: ~50-60% (primarily as glucuronide conjugates of ethinyl estradiol and norethindrone); Fecal: ~40-50% (via biliary elimination)
Approximately 50% of drospirenone is excreted renally (metabolites, with <10% unchanged), and 50% via feces (biliary) after hepatic conjugation. Ethinyl estradiol is primarily excreted renally (60%) and fecally (40%) as glucuronide and sulfate conjugates.
Category C
Category C
Oral Contraceptive
Oral Contraceptive