Kamagra is a brand-name erectile dysfunction medication containing sildenafil citrate. Sildenafil citrate is the active ingredient found in the popular "blue pill," Viagra. Kamagra Online belongs to a class of medications known as phosphodiesterase 5 (PDE5) inhibitors, and it is thought to work similarly to Viagra. Kamagra relaxes blood vessels in the penis in response to sexual stimulation, allowing blood to enter and cause an erection. As ED therapies, regulated medicines like sildenafil, and Kamagra are much safer and more efficient.