Comparative Pharmacology
Head-to-head clinical analysis: ORTHO NOVUM 1 35 28 versus ORTHO TRI CYCLEN LO.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO NOVUM 1 35 28 versus ORTHO TRI CYCLEN LO.
ORTHO-NOVUM 1/35-28 vs ORTHO TRI-CYCLEN LO
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol and norethindrone. Inhibits ovulation by suppressing gonadotropin release (FSH and LH) from the pituitary; increases viscosity of cervical mucus, impeding sperm penetration; alters endometrial lining, reducing implantation likelihood.
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.
1 tablet (norethindrone 1 mg / ethinyl estradiol 35 mcg) orally once daily for 28 consecutive days. Placebo tablets on days 22-28 if included.
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: 5-14 hrs (terminal); ethinyl estradiol: 10-24 hrs. Steady-state achieved within 5-7 days; terminal half-life supports once-daily dosing.
Norelgestromin: 15-20 hours; Ethinyl estradiol: 13-16 hours. Steady-state achieved within 7 days.
Renal 50-60% as metabolites; fecal 30-40% via biliary elimination; <1% unchanged in urine.
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