In a follow-up study of 184 emergency room patients experiencing acute drug reactions, several respondents were inaccessible. In this paper the 83 accessible and 101 nonaccessible patients are compared in order to determine why respondents are often difficult to locate in a follow-up study. Those patients who were the most accessible proved to be primarily young, White males who had been referred to a traditional drug treatment program from the hospital emergency room. Those patients who were the least accessible proved to be primarily White females between 24 and 29 years of age who had not been referred for further treatment.