Gastro-oesophageal reflux disease, which is experienced daily by a significant proportion of individuals, may result in serious sequelae such as erosive oesophagitis. Short-term treatment with acid antisecretory therapy (a proton pump inhibitor or a histamine H(2) receptor antagonist) is highly effective in healing the erosive oesophagitis lesion. However, numerous studies confirm that unless maintenance therapy is initiated virtually all patients will experience oesophagitis relapse within 1 year, as well as an increasing severity of oesophagitis and risk for complications such as Barrett's oesophagus and adenocarcinoma. Studies evaluating the efficacy of proton pump inhibitor and H(2) antagonist maintenance therapy have found that only the proton pump inhibitors significantly reduce the incidence of oesophagitis relapse. Pharmacoeconomic studies have also confirmed that proton pump inhibitor maintenance therapy is cost effective, by virtue of the ability of these agents to reduce the incidence of relapse as well as prolong the time to relapse and increase the number of weeks per year that patients are without symptoms. Lansoprazole, a member of the proton pump inhibitor class of agents, has been extensively studied in the treatment of patients with a variety of acid-related disorders. Among those with erosive oesophagitis, maintenance therapy with lansoprazole 15 or 30mg once daily is highly effective in preventing relapse. Studies have documented that lansoprazole 15 and 30mg once daily for six months prevents oesophagitis relapse in up to 81 and 93% of patients, respectively, with comparable percentages of patients remaining in remission after 1 year of treatment. These high rates of remission have also been observed in studies of patients with lesions that were difficult to heal at baseline (resistant to healing with at least 3 months of H(2) antagonist therapy). Moreover, lansoprazole produces high remission rates regardless of the grade of erosive oesophagitis before acute healing. Among symptomatic patients with heartburn, lansoprazole provides rapid and effective relief of daytime and night-time heartburn and prevents relapse of symptoms. Lansoprazole has a wide margin of safety and is well tolerated when administered as monotherapy in short- and long-term clinical trials. Taken together these data suggest that proton pump inhibitor therapy represents the preferred and ideal long-term management strategy for the patient with erosive oesophagitis. Lansoprazole is a well-established member of this class of agents and, as such, has an extensive body of literature that supports its safety, tolerability and clinical efficacy in preventing relapse in these patients.