The role and limitations of H2-receptor antagonists in the treatment of gastro-oesophageal reflux disease.

Gastro-oesophageal reflux disease (GERD) occurs in up to 44% of adults in the USA. Most individuals do not seek medical help, self-medicating with antacids. Manifestations of GERD range from symptoms without oesophagitis, which constitute the bulk of patients who self-medicate, to active oesophagitis and then to complications such as stricture and ulceration. It is the more severe cases who tend to come to the gastroenterologist, but it must be remembered that reflux symptoms are probably around 5-10 times more common than actual oesophagitis. Since acid in the refluxate is responsible for the bulk of the symptoms and mucosal damage, antacids are often used for quick relief--which of course may not be sustained. More prolonged suppression of acid secretion, such as by a histamine H2-receptor antagonist (H2RA) or a proton pump inhibitor (PPI), is required to give long-lasting symptomatic relief and heal any inflammatory change. H2-receptor antagonists inhibit acid secretion with an effect that lasts for 4-8 h with a single dose, decreasing stimulated acid secretion by around 70%. When treating oesophagitis, the H2RAs suffer from the disadvantage of their relatively short duration of action (compared with PPIs), development of tolerance, and incomplete inhibition of acid secretion in response to a meal. Therefore, it is not easy for the H2RAs to achieve optimum conditions for healing the more severe forms of oesophagitis--even very high doses may fail. In mild GERD the H2RAs have been shown to be effective in relieving symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)