Are oral pde5 agents effective for ve nous leakage

Yes: Yes they are but you need a proper consult in order to get optimal results and it does not happen to be deletereous for other preexisting conditions.

In your legs?: Edema can be caused by heart, liver,kidney failure, obesity, venous valve dysfunction, lymphatic damage, allergic reactions,even filariasis..... there is either too much pressure in the vessel, or too much sodium outside of the vessel, and this draws fluid into the most gravity dependent area. PDE5 could in theory dilate the vein and lower the hydrostatic pressure, decreasing leakage of serum.