Comparative Pharmacology
Head-to-head clinical analysis: KAITLIB FE versus NORTREL 1 35 21.
Peer-Reviewed Evidence
Head-to-head clinical analysis: KAITLIB FE versus NORTREL 1 35 21.
KAITLIB FE vs NORTREL 1/35-21
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
KAITLIB FE (levonorgestrel/ethinyl estradiol/ferrous fumarate) is a combined hormonal contraceptive. Levonorgestrel is a progestogen that suppresses gonadotropin release, inhibiting ovulation. Ethinyl estradiol is an estrogen that stabilizes the endometrium and provides cycle control. The added ferrous fumarate is an iron supplement to treat iron deficiency anemia.
Combination of ethinyl estradiol (estrogen) and norethindrone (progestin) suppresses gonadotropin (FSH and LH) release from the pituitary, inhibiting ovulation, altering cervical mucus to impede sperm penetration, and inducing endometrial changes that reduce implantation likelihood.
One tablet (norethindrone 1 mg and ethinyl estradiol 0.02 mg, with ferrous fumarate 35 mg) orally once daily for 28 days (21 active pills, 7 placebo/iron pills).
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Terminal elimination half-life: 12-15 hours; clinically significant for once-daily dosing
Norethindrone: 5-14 hours; Ethinyl estradiol: 17-24 hours. Steady-state achieved after 10 days.
Renal: 40-60% as unchanged drug; biliary: 20-30% as metabolites; fecal: 10-20%
Renal 50-60% as metabolites, fecal 40-50% as conjugates, <1% unchanged
Category C
Category C
Oral Contraceptive
Oral Contraceptive