Comparative Pharmacology
Head-to-head clinical analysis: PREVEN EMERGENCY CONTRACEPTIVE KIT versus PREVIFEM.
Peer-Reviewed Evidence
Head-to-head clinical analysis: PREVEN EMERGENCY CONTRACEPTIVE KIT versus PREVIFEM.
PREVEN EMERGENCY CONTRACEPTIVE KIT vs PREVIFEM
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
The levonorgestrel component is a progestin that inhibits ovulation and fertilization by altering the cervical mucus and endometrial lining, preventing implantation. The ethinyl estradiol component suppresses gonadotropin release, inhibits ovulation, and alters the endometrium.
PREVIFEM is a combination of ethinyl estradiol, an estrogen, and norgestimate, a progestin. It inhibits ovulation by suppressing gonadotropin release from the pituitary (FSH and LH). Additionally, it increases viscosity of cervical mucus, impeding sperm penetration, and alters the endometrium.
The kit contains levonorgestrel 0.75 mg tablets. The regimen is two tablets: one tablet taken orally as soon as possible within 72 hours of unprotected intercourse, followed by a second tablet taken orally 12 hours later.
One tablet (0.075 mg norgestrel and 0.03 mg ethinyl estradiol) orally once daily at the same time each day for 21 consecutive days, followed by 7 placebo tablets.
None Documented
None Documented
26 hours (range 17-35 hours; clinical: no significant accumulation with single dose).
20-24 hours; steady-state reached in 5 days
Primarily renal (50-60% as metabolites, <1% unchanged) and fecal (30-40% as metabolites).
Renal (60% as metabolites, <10% unchanged), fecal (30%), biliary (10%)
Category C
Category C
Emergency Contraceptive
Emergency Contraceptive