Kamagra and Viagra both contain Sildenafil citrate, a PDE5 inhibitor that works by increasing blood flow to the penis, making it easier for a man to achieve and maintain an erection in response to sexual stimulation. In terms of effectiveness, Kamagra vs Viagra should provide similar results because they both contain the same active ingredient, Sildenafil. If you are considering using Kamagra, it’s crucial to purchase it from a reputable source. However, Viagra remains the more reliable and safer option due to its regulation, clinical evidence, and FDA approval.