Drugs which prevent the formation of acid in the stomach is / are

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for drugs that prevent the formation of acid in the stomach. This indicates that we are looking for medications that reduce stomach acidity or inhibit acid production.

2. **Identifying Relevant Drugs**: One of the most commonly known drugs that prevent acid formation in the stomach is Omeprazole. It is classified as a proton pump inhibitor (PPI), which works by blocking the proton pumps in the stomach lining that produce acid.

3. **Explaining the Mechanism of Action**: Omeprazole and similar drugs function by inhibiting the secretion of gastric acid. This helps in conditions like gastroesophageal reflux disease (GERD), peptic ulcers, and other acid-related disorders.

4. **Mentioning Other Types of Antacids**: While Omeprazole is a specific example, there are also other types of antacids that can neutralize existing stomach acid, such as those containing calcium, magnesium, or aluminum salts. However, these do not prevent acid formation but rather neutralize it.

5. **Conclusion**: Therefore, the primary drug that prevents the formation of acid in the stomach is Omeprazole.

**Final Answer**: The drug that prevents the formation of acid in the stomach is Omeprazole.

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