Antibiotics Flashcards
(17 cards)
What are penicillins?
A group of antibiotics derived from Penicillium fungi effective against a broad range of bacterial infections
Penicillins were among the first antibiotics discovered.
Who discovered penicillin and when?
Alexander Fleming in 1928
This antibiotic was the first widely used and revolutionized the treatment of bacterial infections.
What is the mechanism of action of penicillins?
Inhibits bacterial cell wall synthesis by blocking transpeptidase enzyme, preventing peptidoglycan cross-linking
This leads to cell wall weakening and bacterial lysis.
List the types of penicillin.
- Natural Penicillins: Penicillin G, Penicillin V
- Aminopenicillins: Amoxicillin, Ampicillin
- Penicillinase-Resistant: Methicillin, Nafcillin, Oxacillin, Dicloxacillin
- Extended-Spectrum: Piperacillin, Ticarcillin
Each type has specific uses and characteristics.
What are the indications for natural penicillins?
- Streptococcus spp.
- Some Staphylococcus spp.
- Neisseria meningitidis
These infections are commonly treated with natural penicillins.
What are the indications for aminopenicillins?
- E. coli
- H. influenzae
Aminopenicillins are effective against these bacteria.
What types of infections are penicillinase-resistant penicillins used for?
Staphylococcus infections
These penicillins are designed to resist degradation by penicillinase.
What is the coverage of extended-spectrum penicillins?
- Pseudomonas
- Gram-negative coverage
Extended-spectrum penicillins are used for more resistant bacterial infections.
What is the absorption route for Penicillin V and Amoxicillin?
Oral
Penicillin G is absorbed intravenously.
What is the main route of excretion for penicillins?
Mainly renal, unchanged in urine
This is important for dosing in patients with renal impairment.
What are common side effects of penicillins?
- Allergic reactions (rash to anaphylaxis)
- GI upset
- Superinfections (C. difficile)
- Neurotoxicity (high doses, renal impairment)
Monitoring for these side effects is essential during treatment.
What are the contraindications for using penicillins?
Known hypersensitivity
Caution is also advised in patients with allergies or asthma.
What patient education should be provided regarding penicillin use?
- Complete the full course
- Report allergy symptoms
- May reduce oral contraceptive effectiveness
Ensuring patients understand these points helps improve treatment outcomes.
What should be monitored during prolonged therapy with penicillins?
Renal and hepatic function
Also watch for superinfections.
True or False: Penicillins reduce the efficacy of oral contraceptives.
True
This interaction is important for patient counseling.
What effect do penicillins have on anticoagulants?
Increases anticoagulant effects
Monitoring is required when penicillins are used with anticoagulants.
Fill in the blank: Penicillins block the _______ enzyme to inhibit bacterial cell wall synthesis.
transpeptidase
This enzyme is crucial for peptidoglycan cross-linking.
