Comparative Pharmacology
Head-to-head clinical analysis: BEYAZ versus NORTREL 1 35 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: BEYAZ versus NORTREL 1 35 21.
BEYAZ vs NORTREL 1/35-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination of ethinyl estradiol and drospirenone suppresses gonadotropins (FSH and LH) from the pituitary, inhibiting ovulation, altering cervical mucus, and inducing endometrial changes. Drospirenone is a spironolactone analogue with antimineralocorticoid and antiandrogenic activity.
Combination of ethinyl estradiol (estrogen) and norethindrone (progestin) suppresses gonadotropin (FSH and LH) release from the pituitary, inhibiting ovulation, altering cervical mucus to impede sperm penetration, and inducing endometrial changes that reduce implantation likelihood.
One tablet (drospirenone 3 mg / ethinyl estradiol 0.02 mg) orally once daily for 24 days, followed by 4 days of placebo.
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Drospirenone: approximately 30 hours (terminal). Ethinyl estradiol: approximately 13-15 hours (terminal). Steady-state reached within 10 days. Clinical context: once-daily dosing maintains therapeutic levels with minimal accumulation after 3-4 cycles.
Norethindrone: 5-14 hours; Ethinyl estradiol: 17-24 hours. Steady-state achieved after 10 days.
Urine (45-55% as metabolites), feces (30-40% as metabolites), with enterohepatic recirculation of ethinyl estradiol metabolites.
Renal 50-60% as metabolites, fecal 40-50% as conjugates, <1% unchanged
Category C
Category C
Oral Contraceptive
Oral Contraceptive