udenafil udenafil the drug udenafil is marketed under the trade name zydena. it is within the pde5 inhibitor class (which also includes avanafil, sildenafil, tadalafil, and vardenafil). like other pde5 inhibitors, it is used to treat erectile dysfunction. udenafil was developed by dong-a pharmaceutical. it has fairly rapid onset of action (peak plasma concentration after 1 to 1.5 hours), and has long duration of action (plasma half-life of 11 to 13 hours). udenafil's pharmacokinetics allows once-daily dosage (in addition to on-demand use). typical doses are 100 and 200 mg. udenafil is available in korea, russia, and the philippines. it has not yet been approved for use in the united states by the u.s. food and drug administration. udenafilclinical dataroutes ofadministrationby mouthatc codeg04be11 (who) legal statuslegal status us: not approved in general: ℞ (prescription only) pharmacokinetic dataprotein binding93,9%metabolismliver (mainly cyp3a4)elimination half-life7.3–12.1 hoursexcretionbiliaryidentifiers iupac name 3-(1-methyl-7-oxo-3-propyl-4,7-dihydro-1h-pyrazolopyrimidin-5-yl)-n--4-propoxybenzenesulfonamide cas number268203-93-6 npubchem cid6918523drugbankdb06267 ychemspider5293720 yuniil5ib4xly36keggd10027 nchemical and physical dataformulac25h36n6o4smolar mass516.66 g·mol−13d model (jsmol)interactive image smiles o=c2\n=c(/nc1c(nn(c12)c)ccc)c3cc(ccc3occc)s(=o)(=o)nccc4n(c)ccc4 inchi inchi=1s/c25h36n6o4s/c1-5-8-20-22-23(31(4)29-20)25(32)28-24(27-22)19-16-18(10-11-21(19)35-15-6-2)36(33,34)26-13-12-17-9-7-14-30(17)3/h10-11,16-17,26h,5-9,12-15h2,1-4h3,(h,27,28,32) ykey:iyfnefqtyqpvoc-uhfffaoysa-n y ny (what is this?) (verify)