The most commonly used medications for erectile dysfunction are the phosphodiesterase inhibitors (specifically PDE5 inhibitors which include Sildenafil/Viagra). (FA2020p246)

PDE5 inhibitors (-afils) work by inhibiting the hydrolysis of cGMP by phosphidiesterase, increasing cGMP levels in smooth muscle cells causing relaxation/dilation and allowing the corpora cavernosa to fill with blood (viola, erection).