Studies of the therapeutic efficacy and indications for the use of histamine (H2)-receptor antagonists (H2RAs) in children are reviewed. In adequate dosages, both ranitidine and cimetidine reduce acid output and increase intragastric pH, and H2RAs have been shown to be effective in the treatment of acid-peptic disease. Ranitidine is a more potent drug with a longer duration of action than cimetidine and thus requires less frequent administration. Dosage requirements vary according to age and clinical condition, and children require a relatively higher drug dosage (mg/kg) than adults. There is insufficient information on the long-term paediatric use of famotidine to validate its use in children, and the endocrinological side effects associated with cimetidine therapy in adults essentially preclude its long-term use in children. It is suggested that ranitidine administration is safe and effective in children with acid-peptic disease and should be considered as first-line treatment for children with severe oesophagitis or peptic ulceration and for the prophylaxis of stress ulceration and aspiration pneumonitis.