Comparative Pharmacology
Head-to-head clinical analysis: ORTHO NOVUM 2 21 versus ORTHO TRI CYCLEN 28.
Head-to-head clinical analysis: ORTHO NOVUM 2 21 versus ORTHO TRI CYCLEN 28.
ORTHO-NOVUM 2-21 vs ORTHO TRI-CYCLEN 28
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination of estrogen (ethinyl estradiol) and progestin (norethindrone) inhibits ovulation via negative feedback on the hypothalamic-pituitary-ovarian axis, suppressing gonadotropin release. Additionally, induces changes in cervical mucus and endometrium.
Combination of ethinyl estradiol and norgestimate primarily suppresses gonadotropin (FSH and LH) secretion via negative feedback on the hypothalamic-pituitary-ovarian axis, inhibiting ovulation. Additionally, it increases cervical mucus viscosity and alters endometrial structure to impede fertilization and implantation.
One tablet orally once daily for 21 days followed by 7 days off. Each tablet contains norethindrone 2 mg and ethinyl estradiol 0.1 mg.
One tablet daily for 28 days: 21 active tablets (norgestimate 0.180 mg/ethinyl estradiol 0.035 mg, norgestimate 0.215 mg/ethinyl estradiol 0.035 mg, norgestimate 0.250 mg/ethinyl estradiol 0.035 mg) followed by 7 inert tablets. Route: oral.
None Documented
None Documented
Norethindrone: terminal half-life 5-12 hours; ethinyl estradiol: terminal half-life 7-20 hours (enterohepatic recirculation may prolong effect). Steady-state achieved after 5-7 days.
Norethindrone: ~8 hours; Ethinyl estradiol: ~15 hours (biphasic, terminal: 15-20 hours). Steady-state achieved within 7-14 days.
Renal (approx. 60% as metabolites), fecal (approx. 40% as metabolites). Norethindrone and ethinyl estradiol are extensively metabolized; less than 5% excreted unchanged in urine.
Renal: ~60% (metabolites); Fecal: ~40% (metabolites); unchanged drug <1%
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive