Voltaren is made of a smooth, non-greasy formula that combines a gel and cream (Voltaren Emulgel) for topical application. This specialized formula helps the active ingredient, diclofenac, penetrate through the skin at the site of pain. While most other topicals heat or cool the surface of the skin to mask the pain, Voltaren goes further to treats the pain at its source by blocking the production of pain-signaling chemicals.