Comparative Pharmacology
Head-to-head clinical analysis: ORTHO NOVUM 7 14 28 versus PIRMELLA 1 35.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ORTHO NOVUM 7 14 28 versus PIRMELLA 1 35.
ORTHO-NOVUM 7/14-28 vs PIRMELLA 1/35
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol and norethindrone. Suppresses gonadotropin release (FSH, LH) via negative feedback, inhibiting ovulation. Also increases cervical mucus viscosity and alters endometrial receptivity.
Combination of norethindrone (progestin) and ethinyl estradiol (estrogen) that suppresses gonadotropin secretion via negative feedback on the hypothalamic-pituitary-ovarian axis, inhibiting ovulation. Additionally, causes cervical mucus thickening and endometrial atrophy, reducing sperm penetration and implantation.
One tablet daily for 28 days; each tablet contains norethindrone 0.5 mg and ethinyl estradiol 0.035 mg (days 1-7), norethindrone 0.75 mg and ethinyl estradiol 0.035 mg (days 8-14), norethindrone 1 mg and ethinyl estradiol 0.035 mg (days 15-21), and placebo (days 22-28). Take at same time each day.
One tablet orally once daily for 21 days, followed by 7 placebo tablets during the withdrawal bleed.
None Documented
None Documented
Ethinyl estradiol: ~13-27 h (mean 17 h); Norethindrone: ~5-14 h (mean 8 h). Clinical context: steady-state achieved after ~5 days; half-life supports daily dosing.
Terminal half-life 24–30 hours for ethinyl estradiol; 13–18 hours for norethindrone. Steady state reached after 7–10 days.
Renal: ~50-60% (metabolites); biliary/fecal: ~30-40% (metabolites); unchanged drug <1% in urine.
Renal 60–80% as metabolites (glucuronide conjugates), biliary/fecal 10–20%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive