Prolonged anesthesia in joints and body spaces

The use of a formulation comprising (a) controlled release microparticles comprising a local anesthetic and an effective amount of a biocompatible, biodegradable sustained release polymer selected from polyanhydrides, copolymers of lactic acid and glycolic acid, poly(lactic) acid, poly(glycolic) acid, polyesters, polyorthoesters, proteins, polysaccharides and combinations thereof, providing an in-vitro release of said local anesthetic of from 10 to 60 percent after 24 hours, from 20 to 80 percent release after 48 hours, and from 40 to 100 percent release after 72 hours;

• and (b) a non-toxic augmenting agent in an amount effective to prolong the effect of the local anesthetic in-vivo, for providing pain relief a body space selected from pleura, peritoneium, cranium, mediastinum, pericardium, bursai, epidural, intrathecal, and intraocular, or from intra articular joints selected from knee, elbow, hip, sternoclavicular, temporomandibular, carpal, tarsal, wrist, ankle, and any other joint subject to arthritic conditions, or from bursae selected from acromial, bicipitoradial, cubitoradial, deltoid, infrapetellar, ishchiadica, and other bursa known to those skilled in the art to be subject to pain, and which formulation when administered in-vivo for at least about 24 hours, and preferably for 3-5 days.