Comparative Pharmacology
Head-to-head clinical analysis: CIALIS versus STAXYN.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CIALIS versus STAXYN.
CIALIS vs STAXYN
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Phosphodiesterase-5 (PDE5) inhibitor; increases cGMP levels, causing smooth muscle relaxation and vasodilation in the corpus cavernosum, enhancing erectile function.
Selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). By inhibiting PDE5, sildenafil increases intracellular cGMP levels in the corpus cavernosum, enhancing the relaxant effect of nitric oxide (NO) on smooth muscle cells, thereby facilitating penile erection in response to sexual stimulation.
Tadalafil 10 mg or 20 mg orally as needed at least 30 minutes before sexual activity; maximum dosing frequency once daily. Alternative: 2.5 mg or 5 mg once daily for daily use.
10 mg sublingually as needed, 30–60 minutes before sexual activity. Maximum 1 dose per 24 hours.
None Documented
None Documented
The terminal elimination half-life of tadalafil is approximately 17.5 hours in healthy subjects, which supports once-daily dosing for erectile dysfunction and once-daily use for benign prostatic hyperplasia. This long half-life distinguishes it from other PDE5 inhibitors.
Terminal elimination half-life is approximately 4-5 hours; clinically, no accumulation with once-daily dosing
Following oral administration, tadalafil is predominantly eliminated by hepatic metabolism. The metabolites are excreted mainly in feces (approximately 61% of the dose) and to a lesser extent in urine (approximately 36% of the dose). No unchanged parent drug is detected in urine.
Renal (approximately 90% as metabolites, <2% unchanged); fecal (10%)
Category C
Category C
PDE5 Inhibitor
PDE5 Inhibitor