Voltaren Topical Arthritis Pain Relief Gel helps movement with a specialized formula, designed to penetrate deep through the skin to deliver powerful arthritis pain relief. Containing diclofenac sodium, this nonsteroidal anti-inflammatory drug targets pain directly at the site. Voltaren gel works through a triple effect: relieves arthritis pain, improves mobility and reduces stiffness to provide prescription-strength arthritis joint pain relief over the counter.