Which of the following pairs are bacteriostatic antibiotics ?

Options

A. Pincilin , tetracycline
B. Erythromycin, chloramphinical
C. Oflaxacin, Aminoglycosides
D. Tetracycline , chloromphinical

Answer

To determine which pairs of antibiotics are bacteriostatic, we need to understand the difference between bacteriostatic and bactericidal antibiotics. Bacteriostatic antibiotics inhibit the growth and reproduction of bacteria without directly killing them, while bactericidal antibiotics kill bacteria.

Let's analyze the provided options step by step:

### Step 1: Understand the Definitions
- **Bacteriostatic Antibiotics**: These antibiotics inhibit bacterial growth and reproduction.
- **Bactericidal Antibiotics**: These antibiotics kill bacteria directly.

### Step 2: Analyze Each Option
1. **Option 1: Penicillin and Tetracycline**
- **Penicillin**: This is a bactericidal antibiotic; it kills bacteria by damaging their cell walls.
- **Tetracycline**: This is a bacteriostatic antibiotic; it inhibits bacterial growth.
- **Conclusion**: This pair is not bacteriostatic because it contains a bactericidal antibiotic.

2. **Option 2: Erythromycin and Chloramphenicol**
- **Erythromycin**: This can be either bactericidal or bacteriostatic depending on the concentration and the type of bacteria. However, it is often considered bacteriostatic.
- **Chloramphenicol**: This antibiotic can also exhibit both bactericidal and bacteriostatic properties, but it is primarily considered bacteriostatic in many clinical uses.
- **Conclusion**: This pair can be considered bacteriostatic.

3. **Option 3: Afluxin and Aminoglycosides**
- **Afluxin**: This is a bactericidal antibiotic; it kills bacteria directly.
- **Aminoglycosides**: These are also primarily bactericidal antibiotics; they kill bacteria by inhibiting protein synthesis.
- **Conclusion**: This pair is not bacteriostatic.

4. **Option 4: Tetracycline and Chloramphenicol**
- **Tetracycline**: As established, this is a bacteriostatic antibiotic.
- **Chloramphenicol**: This is also considered bacteriostatic.
- **Conclusion**: This pair is bacteriostatic.

### Final Answer
The pairs that are bacteriostatic antibiotics are:
- **Option 2: Erythromycin and Chloramphenicol**
- **Option 4: Tetracycline and Chloramphenicol**