Which of the following are sulpha drugs?

Options

A. Sulphapyridine
B. Prontosil
C. Salvarsan
D. Nardil

Answer

To determine which of the given options are sulfa drugs, we need to analyze each of the provided names and identify if they belong to the class of sulfonamide antibiotics, commonly known as sulfa drugs.

### Step-by-Step Solution:

1. **Identify the Options**: The options provided are:
- Sulfapyridine
- Prontosil
- Sulfamidocrysodine
- Salvarsan
- Nardyl

2. **Research Each Option**:
- **Sulfapyridine**: This is a known sulfonamide antibiotic used to treat infections. Therefore, it is a sulfa drug.
- **Prontosil**: This is the first sulfa drug discovered and is also a sulfonamide antibiotic. Thus, it is a sulfa drug.
- **Sulfamidocrysodine**: This is another name for a sulfonamide antibiotic, making it a sulfa drug as well.
- **Salvarsan**: This is an arsenic compound used to treat syphilis, not a sulfa drug.
- **Nardyl**: This is a monoamine oxidase inhibitor (MAOI) used in the treatment of depression, and it is not a sulfa drug.

3. **Conclusion**: Based on the analysis, the sulfa drugs from the options are:
- Sulfapyridine
- Prontosil
- Sulfamidocrysodine

The other two options, Salvarsan and Nardyl, are not sulfa drugs.

### Final Answer:
The correct sulfa drugs from the options provided are:
- **Sulfapyridine**
- **Prontosil**
- **Sulfamidocrysodine**