Zhewitra 40 mg is a potent medication for treating erectile dysfunction (ED) in men. It contains Vardenafil, a PDE5 inhibitor, which works by increasing blood flow to the penis to help achieve and maintain an erection during sexual stimulation. Vardenafil inhibits the phosphodiesterase type 5 enzyme (PDE5), allowing increased levels of cyclic GMP (cGMP) in the penile tissues. This leads to relaxed blood vessels and improved blood flow, resulting in a firmer erection.