Polymyxin B

Definition

Polymyxin B is an antibiotic primarily used to treat Gram-negative bacterial infections. It disrupts the bacterial cell membrane, leading to cell death.

5 Must Know Facts For Your Next Test

1. Polymyxin B is particularly effective against Pseudomonas aeruginosa, a common pathogen in skin and eye infections.
2. It is often used in topical formulations, such as ointments and eye drops, due to its nephrotoxicity when administered systemically.
3. Polymyxin B works by binding to the lipopolysaccharides in the outer membrane of Gram-negative bacteria.
4. Resistance to Polymyxin B can occur but is relatively rare compared to other antibiotics.
5. Combination therapy with other antibiotics may be employed to enhance efficacy and reduce resistance development.

Review Questions

• What type of bacteria does Polymyxin B primarily target?
• Why is Polymyxin B typically used in topical formulations rather than systemic administration?
• How does Polymyxin B disrupt bacterial cells?

Related terms

Neomycin: An antibiotic used in combination with Polymyxin B for treating skin infections.

Gram-negative bacteria: A class of bacteria characterized by a thin peptidoglycan layer and an outer membrane containing lipopolysaccharides.

Pseudomonas aeruginosa:

A common Gram-negative bacterium that can cause skin and eye infections.