Comparative Pharmacology
Head-to-head clinical analysis: ORTHO TRI CYCLEN 28 versus ORTHO TRI CYCLEN LO.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO TRI CYCLEN 28 versus ORTHO TRI CYCLEN LO.
ORTHO TRI-CYCLEN 28 vs ORTHO TRI-CYCLEN LO
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
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.
Combination estrogen (ethinyl estradiol) and progestin (norgestimate) oral contraceptive. Suppresses gonadotropin release, inhibiting ovulation; increases cervical mucus viscosity, impeding sperm penetration; alters endometrial lining, reducing implantation likelihood.
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.
One tablet daily orally for 21 days, followed by 7 placebo tablets. Each active tablet contains 0.025 mg ethinyl estradiol and 0.18 mg norelgestromin (days 1-7), 0.215 mg norelgestromin (days 8-14), 0.25 mg norelgestromin (days 15-21).
None Documented
None Documented
Norethindrone: ~8 hours; Ethinyl estradiol: ~15 hours (biphasic, terminal: 15-20 hours). Steady-state achieved within 7-14 days.
Norelgestromin: 15-20 hours; Ethinyl estradiol: 13-16 hours. Steady-state achieved within 7 days.
Renal: ~60% (metabolites); Fecal: ~40% (metabolites); unchanged drug <1%
Renal (∼40% as metabolites, <10% unchanged) and fecal (∼30% as metabolites); conjugated metabolites excreted in bile and undergo enterohepatic circulation.
Category C
Category C
Hormonal Contraceptive
Hormonal Contraceptive