Viagra’s active ingredient is sildenafil citrate. This chemical compound belongs to a class of drugs called phosphodiesterase-5 (PDE5) inhibitors. Sildenafil works by relaxing blood vessels in the penis, increasing blood flow and facilitating an erection.
Understanding Sildenafil Citrate
Sildenafil citrate itself is a white to off-white crystalline powder. Its chemical formula is C22H30N6O4S. Note the presence of sulfur (S) in the formula; it’s a component of the molecule. The molecular weight is approximately 474.5 g/mol. It’s important to understand that the sulfur atom is a part of the molecule’s structure and contributes to its overall function.
Beyond sildenafil citrate, Viagra tablets contain inactive ingredients which act as fillers, binders, and disintegrants to ensure proper tablet formation and dissolution. These inactive ingredients vary slightly depending on the manufacturer and formulation, but commonly include microcrystalline cellulose, croscarmellose sodium, magnesium stearate, and titanium dioxide. These excipients do not contribute to Viagra’s pharmacological action.
Inactive Ingredients: A Closer Look
While the inactive ingredients don’t affect erectile function, understanding their roles is helpful. Microcrystalline cellulose and croscarmellose sodium aid in tablet disintegration, ensuring the sildenafil is released properly. Magnesium stearate acts as a lubricant during tablet compression. Titanium dioxide provides the characteristic white or light-blue color of the tablets.
