In the course of sulfaguanidine therapy of ambulatory patients a significant number of complications were noted, which it is our purpose to report in this paper. The patients treated were 191 soldiers on a tropical isle. At the time of treatment they were either convalescent or contact carriers of Shigella paradysenteriae flexner, W type. By "convalescent carriers" is meant those whose stool cultures, following complete symptomatic recovery from the acute stage of the disease, were found to be positive for the causal organism; the term "contact carriers" is applied to persons who at no time had any acute symptoms but whose stool cultures were positive.
In addition to a fairly large group, some 20 per cent, with subjective complaints, 22 patients (11.5 per cent) in this series developed objective reactions of sufficient severity to necessitate discontinuing sulfaguanidine. No evident correlation was found to exist between previous sulfaguanidine treatment and reactions.