This lesson introduces antibiotics, how they act against bacteria, and why selecting an appropriate agent matters. It also explains antibiotic resistance and surveys important antibiotic classes.
Antibiotics treat bacterial infections. A bactericidal drug kills bacteria directly, whereas a bacteriostatic drug suppresses bacterial growth and multiplication, allowing the immune system to help clear the infection. Antibiotics do not treat viral infections.
All flashcards
What is antibiotic resistance?
A process in which bacteria become less responsive to an antibiotic, through changes such as altered drug targets, drug removal, drug-inactivating enzymes, or shared resistance DNA.
What is a superinfection?
A new infection that can arise when antimicrobial treatment disrupts normal flora and resistant organisms are left to multiply.
What is the function of an antibiogram?
It reports bacterial susceptibility and resistance patterns for a facility or region, helping clinicians choose more appropriate antibiotics.
How do penicillins damage susceptible bacteria?
They bind penicillin-binding proteins and inhibit cell-wall cross-linking, weakening the wall and leading to bacterial cell death.
How does trimethoprim-sulfamethoxazole affect bacteria?
The combination blocks sequential steps in folate metabolism, impairing bacterial production of nucleotides and other essential cellular materials.
Quiz questions
What is the difference between bactericidal and bacteriostatic antibiotics?Answer: Bactericidal drugs kill bacteria; bacteriostatic drugs inhibit their growth.
How can beta-lactamase inhibitors support the action of certain penicillins?Answer: They inhibit enzymes that would otherwise cleave the penicillin beta-lactam ring.
What information does an antibiogram provide?Answer: Local bacterial susceptibility and resistance patterns that can guide antibiotic selection.
Why can broad-spectrum antibiotic use lead to a superinfection?Answer: It can disrupt normal flora, allowing resistant organisms to overgrow and cause a new infection.
Which class is notable for inhibiting bacterial DNA gyrase?Answer: Fluoroquinolones
Based on Pharmacology for Nurses by Tina Barbour-Taylor, Leah Mueller (Sabato), Donna Paris, Dorie Weaver (OpenStax), licensed CC BY 4.0. Adapted into a summary, flashcards and quizzes.