Histamine H2-receptor antagonists.

The first histamine H2-receptor antagonists were developed in the early 1970s, and they have a dominant role in today's management of peptic ulceration. The original regimens using either cimetidine or ranitidine attempted to control acidity across the 24 hours, but more 'modern' regimens use a large single dose of the H2-blocker in the evening, which produces a pulse of decreased intragastric acidity during the night with a normal acidity in the daytime. High-dose regimens using a new generation of extremely potent histamine H2-receptor antagonists may improve ulcer healing rates at 4 weeks, and may be particularly useful for the management of either severe oesophagitis or intractable duodenal ulceration.