Silditop 100 contains Sildenafil citrate as its active ingredient. Sildenafil is a phosphodiesterase type 5 (PDE5) inhibitor, similar to Vardenafil (the active ingredient in Filitra 10). Sildenafil is commonly used to treat erectile dysfunction (ED) by improving blood flow to the penis, which helps men achieve and maintain an erection during sexual stimulation.