The case of a 71-year-old woman who developed generalized weakness, lymphadenopathy, and a skin rash during methyldopa therapy is described. The prompt disappearance of symptoms following the discontinuation of the drug implicates it in the initial triggering of the abnormal lymphoid proliferation. Shortly thereafter, florid immunoblastic lymphadenopathy developed, and the patient subsequently responded to corticosteroid therapy. The frequent occurrence of immunoblastic lymphadenopathy during or shortly after the administration of various therapeutic medications is emphasized. The nature of the disorder and its differential diagnosis are discussed.