LOCAL ANESTHETIC-CONTAINING COMPOSITION FOR TOPICAL PAIN CONTROL COMPRISING POLYION COMPLEX AS ACTIVE INGREDIENT

摘要

PROBLEM TO BE SOLVED: To provide a local anesthetic-containing composition having a long-term pain relief effect in a living body.SOLUTION: A composition comprises a local anesthetic in a polyion complex of a polyanion and, as a polycation, a triblock copolymer containing a poly (ethylene glycol) block (PEG) sandwiched between two blocks containing a plurality of repetitive units in which a cyclic nitroxide radical contained in a pendant group is covalently bonded to a polymer main chain via aminylene (-NH- group).SELECTED DRAWING: Figure 1