Comparative Pharmacology
Head-to-head clinical analysis: HAILEY 1 5 30 versus LEVONEST.
Peer-Reviewed Evidence
Head-to-head clinical analysis: HAILEY 1 5 30 versus LEVONEST.
HAILEY 1.5/30 vs LEVONEST
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination oral contraceptive containing ethinyl estradiol and desogestrel. Ethinyl estradiol suppresses gonadotropin release via negative feedback on the hypothalamic-pituitary axis; desogestrel, a progestin, inhibits ovulation and alters cervical mucus and endometrial receptivity.
Levonorgestrel is a synthetic progestin that inhibits ovulation by suppressing luteinizing hormone (LH) surge, alters cervical mucus to impede sperm penetration, and induces endometrial changes that inhibit implantation.
One tablet (ethinyl estradiol 0.03 mg, levonorgestrel 0.15 mg) orally once daily at the same time each day for 21 days, followed by 7 placebo tablets. For continuous cycling, may take active tablets daily without placebo.
One tablet (levonorgestrel 1.5 mg) orally as a single dose within 72 hours of unprotected intercourse.
None Documented
None Documented
Terminal elimination half-life of ethinyl estradiol is 13-27 hours (mean 17 hours); for norgestimate, active metabolite norelgestromin has half-life 12-30 hours (mean 19 hours). Steady state reached after 7-14 days.
The terminal elimination half-life is approximately 24-30 hours. This relatively long half-life supports once-daily dosing and allows for stable plasma concentrations within 5-7 days of continuous use.
Approximately 40% renal (as metabolites), 32% fecal (as metabolites), and <1% unchanged in urine.
Renal excretion of conjugated metabolites accounts for approximately 60-80% of an administered dose; fecal elimination via bile accounts for 20-40%.
Category C
Category C
Oral Contraceptive
Oral Contraceptive