Comparative Pharmacology
Head-to-head clinical analysis: KELNOR versus YASMIN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: KELNOR versus YASMIN.
KELNOR vs YASMIN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combined oral contraceptive; inhibits ovulation by suppressing gonadotropin release (FSH and LH) primarily via progestational activity; increases viscosity of cervical mucus to inhibit sperm penetration; alters endometrium.
Combination of ethinyl estradiol and drospirenone suppresses gonadotropins, inhibiting ovulation. Drospirenone has antimineralocorticoid activity, reducing water retention, and antiandrogenic activity.
KELNOR (norethindrone acetate and ethinyl estradiol) is a combined oral contraceptive. Typical adult dose: 1 tablet (norethindrone acetate 1 mg/ethinyl estradiol 20 mcg) orally once daily for 21 days, followed by 7 placebo tablets, starting on day 1 of menstrual cycle.
One tablet (ethinyl estradiol 0.03 mg / drospirenone 3 mg) orally once daily for 21 days, followed by 7 days of placebo.
None Documented
None Documented
Terminal elimination half-life 12-15 hours; clinically relevant for once-daily dosing.
Terminal elimination half-life is approximately 30 hours for drospirenone; steady-state concentration is achieved after 10 days of daily dosing.
Primarily renal excretion of unchanged drug (70-80%) and glucuronide conjugate (10-15%); biliary/fecal elimination accounts for <5%.
Approximately 40% renal and 60% fecal after oral administration; metabolites are excreted as glucuronide and sulfate conjugates.
Category C
Category C
Oral Contraceptive
Oral Contraceptive