Deloxolone was devoid of aldosterone-like properties. Deloxolone could be of therapeutic value in peptic ulcer diseases without inducing fluid retention, hypertension and hypokaliemia. Carbenoxolone and deloxolone were orally administered to healthy volunteers in a cross-over double-blind trial. Both the concentration in gastric juice and the output of PGE2, determined by an RIA method in basal conditions and after pentagastrin bolus, increased in drug-treated compared to vehicle-treated subjects thus supporting the hypothesis that cytoprotection might be due to gastric PGE, levels. Moreover, deloxolone induced less marked effects than carbenoxolone on body weight, hematocrit, plasma potassium and proteins, confirming that deloxolone is less similar to aldosterone than the reference drug.