A 4-year retrospective review of 59 consecutive upper extremity abscesses associated with drug abuse by injection is reported. There were 57 patients, with the most common location being the forearm. All abscesses were treated with incision, drainage, and intravenous antibiotics. Seventeen patients required more than one debridement; nine were complicated by fasciitis, osteomyelitis, septic arthritis, or septic tenosynovitis. Thirty-one patients had human immunodeficiency virus testing, and nine results were positive. Bacteriology showed the most common organisms to be streptococcus, Staphylococcus aureus, and Eikenella corrodens. Nineteen percent of the abscesses had anaerobes cultured. Most of the organisms cultured were common oral or skin flora.