Prescribed in 1998 by the FDA, Viagra is from a group of alleged PDE5-inhibitor drugs which also include other surely understood groups like malegra 100 Mg and Levitra. When Phosphodiesterase type 5 (PDE5) does activate, it torments cyclic guanosine monophosphate (cGMP) which results in a restricted flow of blood in the penis, causing Erectile Dysfunction.
For More ED Products: malegra | fildena | vilitra