**Introduction to Neomycin**

**Definition:**  

Neomycin is an aminoglycoside antibiotic derived from *Streptomyces fradiae*. It is widely used for its broad-spectrum antibacterial properties, particularly against Gram-negative and some Gram-positive bacteria.

**Functions:**  

1. **Antibacterial Action:** Inhibits bacterial protein synthesis, effectively killing or suppressing bacterial growth.  

2. **Infection Prevention:** Used to prevent infections in wounds and surgical sites.  

3. **Topical and Oral Use:** Available in topical creams, ointments, and oral formulations for gastrointestinal infections.  

**Applications:**  

1. **Medical Use:** Treats skin infections, eye infections, and hepatic encephalopathy.  

2. **Veterinary Medicine:** Used to treat bacterial infections in animals.  

3. **Agricultural Use:** Applied as a pesticide to control bacterial diseases in crops.