Eriacta 100 mg is a medication used to treat erectile dysfunction (ED). Its primary ingredient is sildenafil citrate, which is also found in Viagra. Sildenafil citrate inhibits the enzyme phosphodiesterase type 5 (PDE5). This leads to an increase in cyclic guanosine monophosphate (cGMP), which relaxes the smooth muscle in the blood vessels of the penis, thereby increasing blood flow and facilitating an erection in response to sexual stimulation.