AbstractThe prevalence of peptic ulcer in cirrhotic patients is similar to that reported for the general population. Although gastric acid outputs ar normal or lower in cirrhotic subjects compared with non‐cirrhotics, the frequency of non‐response to histamine H2‐receptor antagonists is higher. Peptic ulcer disease in the cirrhotic seems to pursue a more virulent course compared with that in the non‐cirrhotic subject.Peptic ulcer prevalences in patients dying of uraemia or in uraemic patients on maintenance dialysis treatment are comparable with those in the general population. However, the frequency of peptic ulcer, especially complicated ulcer, is increased following renal transplantation. Ulcer complications in this context are associated with a high mortality rate. Pre‐transplant risk factors for subsequent development of peptic ulcer remain to be identified and the value of histamine H2‐receptor antagonists in prophylaxis is as y