H2 antagonist

H₂ antagonists, also called H₂ blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H₂ antagonists can be used in the treatment of dyspepsia, but have been surpassed by the more effective proton pump inhibitors for that indication. They are also used to treat peptic ulcer disease and gastroesophageal reflux disease.