The histochemical features of muscle injury and repair were examined in an experimental form of acute alcoholic myopathy in the rat. Typical features of rhabdomyolysis were found, which were indicated by scattered muscle fiber necrosis followed by sequential phases of fiber degeneration, phagocytosis, and regeneration. Nests of small, regenerated, or split fibers remained 2 months after the episode of acute myopathy. Vulnerability of type 1 fibers to alcohol-induced muscle injury was evident by selective involvement of muscles with type 1 fiber predominance and by the fact that regenerating fibers were virtually exclusively type 1. The histologic features of myopathy in this model closely parallel those in human acute alcoholic myopathy.