Comparative Pharmacology
Head-to-head clinical analysis: ETHINYL ESTRADIOL AND NORELGESTROMIN versus OGEN 625.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ETHINYL ESTRADIOL AND NORELGESTROMIN versus OGEN 625.
ETHINYL ESTRADIOL AND NORELGESTROMIN vs OGEN .625
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination contraceptive: estrogen (ethinyl estradiol) suppresses gonadotropin release via negative feedback on pituitary; progestin (norelgestromin) thickens cervical mucus and inhibits ovulation.
Estrogen replacement therapy; estrogen binds to estrogen receptors, which then translocate to the nucleus and modulate gene transcription, leading to effects such as proliferation of the endometrium and regulation of gonadotropin secretion.
One transdermal patch (releasing 0.035 mg ethinyl estradiol and 0.150 mg norelgestromin per 24 hours) applied once weekly for 3 weeks, followed by 1 week patch-free.
0.625 mg orally once daily
None Documented
None Documented
Ethinyl estradiol has a terminal elimination half-life of approximately 13-27 hours (mean ~17 hours). Norelgestromin has a terminal half-life of about 28 hours. These half-lives support once-weekly dosing of the transdermal system, achieving steady-state by the second application.
Estrone: 10-24 hours; equilin: 12-18 hours; terminal half-life supports once-daily dosing.
Ethinyl estradiol and norelgestromin are excreted primarily via urine and feces. Ethinyl estradiol undergoes extensive metabolism; about 40% is excreted in urine and 60% in feces as glucuronide and sulfate conjugates. Norelgestromin is metabolized to norgestrel and other metabolites; approximately 45% is excreted in urine and 35% in feces.
Renal (primarily as glucuronide and sulfate conjugates, ~50-80% of a dose), fecal (~10-20%), with enterohepatic recirculation.
Category D/X
Category C
Estrogen
Estrogen