Among the following which is not a bacteriostatic antibiotic

Options

A. Tetracycline
B. Penicillin
C. Erythromycin
D. Chloramphenicol

Answer

To determine which of the following antibiotics is not a bacteriostatic antibiotic, we first need to understand the definitions of bacteriostatic and bactericidal antibiotics.

### Step-by-Step Solution:

1. **Define Bacteriostatic Antibiotics**:
- Bacteriostatic antibiotics are those that inhibit the growth and reproduction of bacteria but do not kill them outright. They essentially "stop" the bacteria from multiplying.

2. **Define Bactericidal Antibiotics**:
- Bactericidal antibiotics, on the other hand, kill bacteria directly. They are effective in eliminating the bacteria rather than just inhibiting their growth.

3. **Identify the Antibiotics**:
- The question lists several antibiotics. We need to categorize each based on whether they are bacteriostatic or bactericidal.
- **Tetracycline**: This antibiotic is known to be bacteriostatic as it inhibits bacterial growth.
- **Penicillin**: This antibiotic is classified as bactericidal because it kills bacteria directly.
- **Erythromycin**: This antibiotic is also bacteriostatic and works by inhibiting bacterial growth.
- **Chloramphenicol**: This is a broad-spectrum antibiotic that is bacteriostatic as it inhibits the growth of a wide range of bacteria.

4. **Conclusion**:
- Among the antibiotics listed, **Penicillin** is the one that is not a bacteriostatic antibiotic; it is bactericidal.

### Final Answer:
The antibiotic that is not a bacteriostatic antibiotic is **Penicillin**.

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