Bone marrow biopsies from 30 alcohol-dependent individuals hospitalized for detoxification were investigated. Typical alcohol-induced bone marrow changes were found and served to define alcohol-induced bone marrow damage as a nosological entity. The findings took the form of heightened ineffective erythropoie-sis associated with impaired iron utilization, vacuolated proerythroblasts, multinuclear erythroblasts, megalo-blasts and iron-containing plasma cells as well as vacuolated precursor cells of the granulocytopoietic series. In the differential diagnosis, alcohol-induced bone marrow damage is to be distinguished from the myelodysplas-tic syndrome of the RA and RARS form. Alcohol-induced bone marrow damage is reversible. Bone marrow cell cultures performed in our cases are normal, showing that the toxic defect probably does not reside in the stem cell but is more peripheral. Normal bone marrow cell culture may be a typical feature of alcohol-induced bone marrow damage