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How are cimetidine and ranitidine used in treating peptic ulcers?
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antihistamine
Antihistamines such as Benadryl (diphenhydramine) and Claritin (loratadine) can be purchased without prescriptions. Both of those agents act by blocking H1 receptors. However, whereas Benadryl binds to those receptors in the central nervous system (CNS), causing drowsiness, Claritin does not readily enter the CNS and thus does not normally cause drowsiness.
Cimetidine and ranitidine are classified as H2 receptor antagonists, which are drugs that block the action of histamine at its H2 receptors to reduce the secretion of gastric acid in the stomach.123
In the treatment of peptic ulcers, these medications are utilized in the following ways:
- H. pylori-induced ulcers: When ulcers are caused by the bacterium Helicobacter pylori, cimetidine and ranitidine are used in combination with antibiotics to stop acid secretion, allowing the mucosal lining to heal.14
- NSAID-induced ulcers: For ulcers resulting from the long-term use of nonsteroidal anti-inflammatory drugs, these blockers are used to manage the condition if the withdrawal of the NSAID is not possible.4
- General management: By inhibiting the stimulation of acid secretion by histamine, gastrin, and food, these drugs help treat conditions involving the hypersecretion of gastric acid, thereby promoting the healing of ulcers and preventing their recurrence.423