Which of the following is bacteriostatic ?

Options

A. Penicillin
B. Erythromycin
C. amino glycoside
D. ofloxacin

Explanation

To determine which of the following options is bacteriostatic, we need to understand the definitions of bacteriostatic and bactericidal antibiotics.

1. **Understanding Bacteriostatic and Bactericidal:**
- Bacteriostatic antibiotics inhibit the growth and reproduction of bacteria. They do not kill the bacteria directly but prevent them from multiplying.
- Bactericidal antibiotics, on the other hand, kill bacteria by destroying their cell walls or interfering with their metabolic processes.

2. **Analyzing the Options:**
- **Option 1: Penicillin** - This is a bactericidal antibiotic. It works by disrupting the synthesis of the bacterial cell wall, leading to the death of the bacteria.
- **Option 2: Erythromycin** - This is a bacteriostatic antibiotic. It inhibits bacterial protein synthesis, thereby stopping the growth and reproduction of bacteria.
- **Option 3: Aminoglycoside** - This class of antibiotics is also bactericidal. It works by binding to bacterial ribosomes and causing misreading of mRNA, leading to the death of the bacteria.
- **Option 4: Ofloxacin** - This is a bactericidal antibiotic that works by inhibiting bacterial DNA gyrase, which is essential for DNA replication.

3. **Conclusion:**
- Among the options provided, **Erythromycin** is the only bacteriostatic antibiotic.

**Final Answer: Erythromycin is bacteriostatic.**

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