Comparative Pharmacology
Head-to-head clinical analysis: CYTADREN versus LETROZOLE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CYTADREN versus LETROZOLE.
CYTADREN vs LETROZOLE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Aminoglutethimide inhibits the conversion of cholesterol to pregnenolone, thereby blocking adrenal steroidogenesis. It also inhibits aromatase, reducing estrogen synthesis.
Letrozole is a nonsteroidal aromatase inhibitor. It inhibits the aromatase enzyme, which converts androgens to estrogens, thereby reducing estrogen levels in postmenopausal women and suppressing estrogen-dependent tumor growth.
200 mg orally once daily
2.5 mg orally once daily
None Documented
None Documented
Terminal elimination half-life: 3–4 hours in adults with normal renal function; prolonged to 8–12 hours in end-stage renal disease.
Clinical Note
moderateLetrozole + Digoxin
"Letrozole may decrease the cardiotoxic activities of Digoxin."
Clinical Note
moderateLetrozole + Digitoxin
"Letrozole may decrease the cardiotoxic activities of Digitoxin."
Clinical Note
moderateLetrozole + Deslanoside
"Letrozole may decrease the cardiotoxic activities of Deslanoside."
Clinical Note
moderateLetrozole + Acetyldigitoxin
"Letrozole may decrease the cardiotoxic activities of Acetyldigitoxin."
Terminal elimination half-life approximately 45 hours (range 42-52 hours). Steady-state achieved in 2-6 weeks with daily dosing.
Renal: ~60% as unchanged drug; biliary/fecal: ~25% as metabolites; minor via respiration.
Primarily hepatic metabolism (CYP3A4, CYP2A6) with 90% excreted in urine as metabolites (glucuronide conjugates) and 10% in feces. <6% excreted unchanged in urine.
Category C
Category D/X
Aromatase Inhibitor
Aromatase Inhibitor