Vigora 50 mg is a medication containing sildenafil citrate and is used to treat erectile dysfunction (ED) in men. Sildenafil citrate is a phosphodiesterase type 5 (PDE5) inhibitor that works by increasing blood flow to the penis, helping men achieve and sustain erections when sexually aroused. Vigora 50 is a brand name for sildenafil citrate, and it's produced by the pharmaceutical company German Remedies, which is a part of the Zydus Cadila Group. While I don't have the exact date of when Vigora 50 mg was introduced as a medication, sildenafil citrate itself was first introduced as the revolutionary medication Viagra by Pfizer in March 1998. Since then, various generic versions of sildenafil, like Vigora, have been developed and introduced to the market. If you're interested in the specific launch date of Vigora 50 mg, I recommend checking with reliable medical sources or directly contacting the manufacturer or relevant authorities for accurate and current information.