US Patent 8114434 Diclofenac sodium patches for topical treatment of pain

The invention provides an analgesic anti-inflammatory patch of a hydrophobic type for topical application containing, in a Pressure Sensitive Adhesive(PSA), diclofenac sodium, pyrrolidone or a derivative thereof, a polyhydric alcohol fatty acid ester, and an organic acid. The patch exerts the following effects:(1) diclofenac sodium is effectively and continuously released from a Pressure Sensitive Adhesive(PSA) and percutaneously absorbed, thereby attaining sustained, excellent pharmaceutical and pharmacological effects;(2) the patch per se has high tackiness and safety; and(3) diclofenac sodium remains stable in the Pressure Sensitive Adhesive(PSA).