5.2 Antibiotics - Principles of Prescribing Flashcards
What types of Antibiotics are there?
Protein Synthesis
Cell Wall Inhibitors
DNA and RNA synthesis
When do we use antibiotics?
Prophylaxis
Treat a Severe Infection
What are the 3 types of prophylaxis
Peri-Operative
Short Term - if near someone with meningitis/TB
Long Term - asplenic/immunocomprimised patients
What infections do we treat?
Empirical - if severe
A proven, cultured infection
What do you think of when choosing an antibiotic?
What is the microorganism? Resistant Strains? Where is the infection - route to give What is it succeptible to? Course and Dose required Patient Factors - age, sex, immune/general health Cost Efficacy
What do you have to be aware of after giving an antibiotic?
Side Effects
DDIs
Allergic Response - penicillin, pseudoanaphylactoids
Effect on Flora - e.g. risk of C difficile
When do you monitor a drug?
When it is very potent
When the patient is renally/hepatically impaired
When there is a narrow TW
Specific antibiotics you monitor?
Vancomycin
Gentomycin (aminoglycosides - nephro/ototoxic)
How do you measure antibiotic activity?
Disc Sensitivity (qualitative) Minimum Inhibitory Concentration (quantitative)
What are the 2 methods of resistance?
Horizontal Gene Transfer
Chromosomal Gene Mutation
Mechanisms of resistance?
Increased Efflux/Decreased Uptake
Enzyme alteration - beta lactamase
Alteration of drug target site
What is antimicrobial stewardship?
Responsible use of drugs to increase efficacy, decrease cost and drug resistance
How do we know the right dosage?
Depends on PK- Oral, IV, IM, and its distribution
Depends on PD - is it concentration or time dependent killing
What is infection control?
Prevention of infection and reducing severity by preventing the bacteria from being exposed to antibiotics and preventing the spread (PPE, gloves, handwashing etc)
