Lecture Notes: Fluoroquinolone Antibiotics

Introduction

• Focus on antibiotics that impact microbial DNA and RNA synthesis.
• Additional antibiotics discussed: Metronidazole and Quinolones.

Metronidazole (Flagyl)

• Functions as both an antibiotic and an antiprotozoal.
• Interferes with DNA replication.
• Important for understanding its dual role.

Quinolones

• Originated as byproducts in chloroquine (an antimalarial drug) production.
• Nalidixic Acid:
  • Only quinolone to know from this group.
  • Effective solely against urinary tract infections (UTIs).

Fluoroquinolones

• Chemically modified versions of quinolones.
• Very significant in medical treatment.

Examples

• Ciprofloxacin
• Levofloxacin

Mechanism of Action

• Affect DNA gyrase enzyme:
  • Crucial for preventing coil formation during DNA unwinding and replication.
  • Different from human enzymes, making it selectively toxic to bacteria.

Uses

• Treat various infections including:
  • Respiratory infections
  • Abdominal infections
  • Skin infections
• Broad-spectrum action effective against both gram-positive and gram-negative bacteria.
• Commonly prescribed due to their broad spectrum and effectiveness.

Conclusion

• Ciprofloxacin highlighted as a major fluoroquinolone.
• Nalidixic Acid and fluoroquinolones collectively form the nucleic acid synthesis inhibiting antibiotic group.

"I hope this helps, have a wonderful day! Be blessed!" - Closing remarks by Dr. O