How is acidity cured with cimetidine or ranitidine ?

Explanation

### Step-by-Step Solution:

1. **Understanding Acidity**: Acidity in the stomach is primarily caused by the secretion of hydrochloric acid (HCl), which is regulated by histamine. When histamine binds to its receptors in the stomach lining, it stimulates the production of HCl.

2. **Role of Cimetidine and Ranitidine**: Cimetidine (also known as Tagamet) and Ranitidine (also known as Zantac) are medications that belong to a class of drugs called H2 receptor antagonists. These drugs are specifically designed to block the H2 receptors in the stomach.

3. **Mechanism of Action**: By blocking the H2 receptors, cimetidine and ranitidine prevent histamine from binding to these receptors. This inhibition reduces the stimulation of HCl secretion, leading to a decrease in the overall acidity in the stomach.

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