Select the correct statement(s) about climetidine andrantitidine.

Options

A. These are antihistamine drugs
B. These prevent the excess production of HCl in the stomach
C. Both prevent the interaction between histamineand receptor of stomach wall
D. All of the above are correct statements

Answer

To solve the question regarding the correct statements about cimetidine and ranitidine, we will analyze the properties and functions of these drugs step by step.

### Step-by-Step Solution:

1. **Understanding the Drugs**:
- Cimetidine and ranitidine are both classified as H2 (histamine-2) receptor antagonists. They are used to treat conditions related to excess stomach acid, such as peptic ulcers and gastroesophageal reflux disease (GERD).

2. **Mechanism of Action**:
- These drugs work by blocking the H2 receptors located on the parietal cells of the stomach lining. Histamine, when it binds to these receptors, stimulates the secretion of gastric acid (HCl). By blocking this interaction, cimetidine and ranitidine reduce the production of gastric acid.

3. **Indications**:
- Both cimetidine and ranitidine are indicated for the treatment of conditions caused by excessive stomach acid, such as peptic ulcers, Zollinger-Ellison syndrome, and GERD.

4. **Comparison of Efficacy**:
- While both drugs serve similar purposes, they differ in potency and side effects. Ranitidine is generally considered to be more potent and has fewer side effects compared to cimetidine.

5. **Side Effects**:
- Cimetidine has been associated with more side effects, including potential interactions with other medications due to its effect on liver enzymes. Ranitidine, on the other hand, has a better safety profile.

### Conclusion:
Based on the analysis, the correct statements about cimetidine and ranitidine are:
- Both are antihistamine drugs (specifically H2 receptor antagonists).
- They prevent the interaction between histamine and the receptors on the stomach wall, thereby reducing the secretion of hydrochloric acid.