Comparative Pharmacology
Head-to-head clinical analysis: LEVLITE versus NORLESTRIN 21 2 5 50.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEVLITE versus NORLESTRIN 21 2 5 50.
LEVLITE vs NORLESTRIN 21 2.5/50
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Levonorgestrel is a progestin that suppresses ovulation by inhibiting gonadotropin release (LH and FSH) and alters cervical mucus, endometrial thickness, and tubal motility.
Combination oral contraceptive containing an estrogen (ethinyl estradiol) and a progestin (norethindrone acetate). Inhibits ovulation by suppressing gonadotropin release. Increases viscosity of cervical mucus, impeding sperm penetration, and alters endometrial receptivity.
One tablet (levonorgestrel 0.1 mg, ethinyl estradiol 0.02 mg) orally once daily for 21 days, followed by 7 placebo tablets.
One tablet orally once daily for 21 days, followed by 7 days off, then repeat.
None Documented
None Documented
Terminal elimination half-life: 21-28 hours; clinical context: permits once-daily dosing
Norethindrone: 8 hours (terminal); Ethinyl estradiol: 13 hours (terminal). Clinical context: Steady-state achieved after 3-5 days; dosing interval based on once-daily administration.
Renal: ~50% (30% as unchanged drug, 20% as metabolites); Fecal: ~40%; Biliary: minor
Renal: 50-60% as metabolites (glucuronide and sulfate conjugates of norethindrone and ethinyl estradiol); fecal: 30-40% via biliary elimination; <1% unchanged.
Category C
Category C
Oral Contraceptive
Oral Contraceptive