Comparative Pharmacology
Head-to-head clinical analysis: ETHYNODIOL DIACETATE AND ETHINYL ESTRADIOL versus SAFYRAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: ETHYNODIOL DIACETATE AND ETHINYL ESTRADIOL versus SAFYRAL.
ETHYNODIOL DIACETATE AND ETHINYL ESTRADIOL vs SAFYRAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Combination hormonal contraceptive: ethynodiol diacetate is a progestin that suppresses gonadotropin secretion (LH and FSH) via negative feedback on the hypothalamic-pituitary axis, inhibiting ovulation; ethinyl estradiol is an estrogen that stabilizes the endometrium and increases cervical mucus viscosity, impeding sperm penetration.
Safyral is a combination of ethinyl estradiol and drospirenone. Ethinyl estradiol is an estrogen that suppresses gonadotropin release, preventing ovulation. Drospirenone is a progestin with anti-mineralocorticoid activity, which may reduce fluid retention, and anti-androgenic activity, which may improve acne. It also increases cervical mucus viscosity, impeding sperm penetration.
1 tablet (1 mg ethynodiol diacetate / 35 mcg ethinyl estradiol) orally once daily for 21 days, followed by 7 placebo days.
One tablet (drospirenone 3 mg/ethinyl estradiol 0.03 mg) orally once daily for 24 days, followed by 4 days of placebo.
None Documented
None Documented
Ethynodiol diacetate: 12-14 hours; ethinyl estradiol: 13-27 hours (mean ~17 hours). Steady-state achieved after 3-4 days.
16.3 hours (range 12-21 hours) for drospirenone; 32.5 hours (range 24-42 hours) for ethinyl estradiol (EE); clinical context: steady-state achieved after 10 days for drospirenone, 7 days for EE
Renal (approximately 40% as metabolites), fecal (approximately 60% as metabolites). Ethynodiol diacetate is extensively metabolized; less than 1% excreted unchanged.
Urine (40% as metabolites, 20% unchanged; fecal 30% as metabolites; biliary excretion contributes to enterohepatic circulation, prolonging elimination)
Category D/X
Category C
Estrogen
Oral Contraceptive Progestin/Estrogen