Principles of Antibiotic Use

Question 1

define prophylactic

Answer 1

intended to prevent disease

Question 2

define empirical

Answer 2

based on observation or experience for the best guess

Question 3

what are the 3 principles of antibiotic use?

Answer 3

• clinically effective
• safe
• cost effective

Question 4

2 reasons why antimicrobials may be prescribed?

Answer 4

treat infection
prevent infection - prophylaxis

Question 5

what questions should you ask before prescribing?

Answer 5

1. infection present and diagnosis?
2. requires antibiotics?
3. aetiology?
4. is there diagnostic evidence?
5. best antibiotic to use?
6. multiple antibiotics required?
7. route of administration?
8. dosage?
9. does the therapy need to be modified based on culture result?
10. time?
11. resistance?
12. patient considerations.

Question 6

why should you know if it requires antibiotics?

Answer 6

• benefits must outweigh the risks
• will the patient improve from usage?

Question 7

what can be collected from the patient before treatment to indicate the aetiology?

Answer 7

• pus sample
• bone sample
• blood culture

Question 8

when would you need a combination of antibiotics? (3)

Answer 8

• infections with multiple organisms
• when you need to limit the emergence of resistance
  -Febrile leukopaenic patients = low neutrophil count - cant fight infection

Question 9

what problems can arise from prescribing multiple antibiotics?

Answer 9

• cost
• antagonism - active hostility, they dont work
• increased toxicity, allergy and resistance

Question 10

what are the principles of directed antimicrobial therapy?

Answer 10

• use lab investigations for microbiological diagnosis

Question 11

what are the principles of empirical antimicrobial therapy?

Answer 11

use history and examination
- use clinical diagnosis

Question 12

what are pharmacokinetic parameters?

Answer 12

they describe drug absorption, distribution, metabolic and elimination

BASC explores how the body reacts to a drug

Question 13

how should dosage be determined?

Answer 13

• based on concentration and time
• both have to exceed the MIC - no useful microbial activity

Question 14

what do you have to consider with the dosage?

Answer 14

• minimal side effects
• lowers cost
• specific dosage for neonates, children and adults
• monitor the levels

Question 15

how is the bacterial elimination half life determined?

Answer 15

the time taken for plasma concentration to reduce by 50%

Question 16

how do you modify therapy based on culture result?

Answer 16

change to the narrowest spectrum that is antimicrobial active against the causative organism = directed therapy

Question 17

what has to be considered for the patient?

Answer 17

• pregnancy and lactation
• renal function
• liver function
• other medical problems

Question 18

how many antibacterial prescriptions were dispensed by pharmacists in 2014?

Answer 18

3.7 million

Question 19

In 202, how much did antibiotic consumption increase by compared to the previous year in dental prescribing?

Answer 19

22.1%

Question 20

what is AMS?

Answer 20

antimicrobial stewardship

• a term to describe the optimal use of antimicrobials to improve patient outcome and reduce antimicrobial resistance

Question 21

what is start smart, then focus?

Answer 21

start smart?
- use antibiotics if evidence of infection
- use local guidelines
- note indication, duration and review
- obtain the cultures
- use single dose antibiotics for surgical prophylaxis

focus - 48 hours in
- stop if no evidence of infection
- switch from intravenous to oral
- change antibiotics - broader or narrower
- review patient again at 72 hrs

Question 22

what is prophylaxis?

Answer 22

antibiotics are given to prevent infection follow procedure

• usually single dose
• spectrum covers most pathogens