Comparative Pharmacology
Head-to-head clinical analysis: FINASTERIDE AND TADALAFIL versus STENDRA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FINASTERIDE AND TADALAFIL versus STENDRA.
FINASTERIDE AND TADALAFIL vs STENDRA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Finasteride is a 5α-reductase inhibitor that inhibits conversion of testosterone to dihydrotestosterone (DHT). Tadalafil is a phosphodiesterase-5 (PDE5) inhibitor that enhances nitric oxide-mediated vasodilation by increasing cyclic guanosine monophosphate (cGMP) in smooth muscle.
Selective inhibitor of phosphodiesterase type 5 (PDE5), enhancing cyclic guanosine monophosphate (cGMP) accumulation in corpus cavernosum, leading to smooth muscle relaxation and increased penile blood flow.
One capsule containing finasteride 5 mg and tadalafil 5 mg orally once daily.
50 mg orally once daily as needed, 1 hour before sexual activity. Maximum dose 100 mg. Maximum frequency once daily.
None Documented
None Documented
Finasteride: 6-8 hours (elderly ~8 hours); Tadalafil: 17.5 hours (enables once-daily dosing).
Terminal elimination half-life is approximately 4 hours in healthy subjects; may be prolonged in hepatic impairment (Child-Pugh B: up to 6 hours) or with concomitant CYP3A4 inhibitors.
Finasteride: 57% feces, 39% urine (metabolites); Tadalafil: 36% urine, 61% feces (mostly metabolites).
Fecal (approximately 63%) and renal (approximately 21%) as metabolites; less than 2% excreted unchanged in urine.
Category A/B
Category C
PDE5 Inhibitor
PDE5 Inhibitor