How to Choose an Antibiotic
Before deciding whether to prescribe an antibiotic there are a number of
things to consider and questions to ask. Firstly:
Empirical antibiotic guidelines are established by answering many of the questions below. It is essential to understand the relevance of these questions and the effect of the answers. Relying on empirical antibiotic guidelines without knowing why or how these guidelines are produced can be dangerous and is poor practice.
things to consider and questions to ask. Firstly:
- Make sure you know normal flora and the causes of common infections
- Know your specialities serious and common infections, the micro-organisms that cause these and the usual treatments for them
- Use the British National Formulary (BNF) for interactions, cautions and contraindications as well as dosing information
- Discuss patients with your own senior team members and Consultant
- Know your own hospital’s empirical antibiotic guidelines for your specialty
Empirical antibiotic guidelines are established by answering many of the questions below. It is essential to understand the relevance of these questions and the effect of the answers. Relying on empirical antibiotic guidelines without knowing why or how these guidelines are produced can be dangerous and is poor practice.
Prophylaxis vs. Treatment
Prophylaxis is the use of antibiotics to prevent infection of a previously uninfected site.
Primary Prophylaxis
• Aims to prevent initial infection e.g. surgical prophylaxis
• Duration – prophylactic antibiotics usually required for <24 hours
• Only required whilst ongoing entry of bacteria into sterile body sites e.g. at the time of surgery
Secondary Prophylaxis
• Aims to prevent recurrent episodes of infection
• Duration – usually long courses of antibiotics at reduced doses e.g. post-splenectomy, rheumatic fever, recurrent UTIs in children
Treatment
Treatment is the use of antibiotics to eliminate infection from an already infected site. Treatment and duration of treatment varies between clinical conditions (see section - Clinical Scenarios for individual conditions).
Primary Prophylaxis
• Aims to prevent initial infection e.g. surgical prophylaxis
• Duration – prophylactic antibiotics usually required for <24 hours
• Only required whilst ongoing entry of bacteria into sterile body sites e.g. at the time of surgery
Secondary Prophylaxis
• Aims to prevent recurrent episodes of infection
• Duration – usually long courses of antibiotics at reduced doses e.g. post-splenectomy, rheumatic fever, recurrent UTIs in children
Treatment
Treatment is the use of antibiotics to eliminate infection from an already infected site. Treatment and duration of treatment varies between clinical conditions (see section - Clinical Scenarios for individual conditions).
How to Prescribe an Antibiotic
• Name of Antibiotic
- This should be the generic name, not a specific product name
• Indication
- In order to know if the stop date is correct, you need to know why the antibiotic has been prescribed
• Start Date
- This is the date the antibiotic was first prescribed NOT the date the prescription was re-written
• Frequency of Dosing
- Antibiotics need to be spaced out evenly in order to maintain therapeutic levels in a patient
• Stop or Review Date
- Should be set at the time of prescribing based on the original diagnosis, e.g. CAP is
diagnosed and treated for 7 days
• Signature
• Name
• GMC number
- This should be the generic name, not a specific product name
• Indication
- In order to know if the stop date is correct, you need to know why the antibiotic has been prescribed
• Start Date
- This is the date the antibiotic was first prescribed NOT the date the prescription was re-written
• Frequency of Dosing
- Antibiotics need to be spaced out evenly in order to maintain therapeutic levels in a patient
• Stop or Review Date
- Should be set at the time of prescribing based on the original diagnosis, e.g. CAP is
diagnosed and treated for 7 days
• Signature
• Name
• GMC number
Antibiotic Spectrum of activity
Click for larger image
Click for larger image
Topics in Antibiotics:
All these topics are covered in the book...Ready to buy your copy? Click here to buy your copy of "Microbiology Nuts & Bolts" Its updated and amazingly only slightly larger considering its got 1/3 more in it! (11cmx18cmx2.5cm).
- Antimicrobial Stewardship
- How Antibiotics Work - Mechanisms of Action
- How to Choose an Antibiotic
- Prophylaxis vs. Treatment
- How to Prescribe an Antibiotic
- The Daily Review of Antibiotic Therapy
- Reasons for Failing Antibiotic Therapy
- Intravenous to Oral Switching of Antibiotics
- Therapeutic Drug Monitoring (TDM)
- Interpretation of TDM
- Antibiotic Dosing in Adult Renal Impairment
- Adjustment of Antibiotic Doses in Adult Renal Impairment
- Antibiotic Dosing in Obesity
- What is Antibiotic Resistance?
- How Resistance Occurs - Mechanisms of Resistance
- How is Antibiotic Resistance Spread?
- How is Antibiotic Resistance Detected in the Laboratory?
- Table of Antibiotic Spectrum of Activity
- Table of Antibiotic Tissue Penetration
- Allergy to Beta-Lactam Antibiotics
- Including pages on each: Penicillins, Cephalosporins, Carbapenems and Aztreonam, Trimethoprim and Co-Trimoxazole (Septrin), Erythromycin, Clarithromycin, Azithromycin and Clindamycin, Gentamicin, Amikacin and Tobramycin, Ciprofloxacin and Levofloxacin, Vancomycin and Teicoplanin, Daptomycin, Metronidazole, Doxycycline, Tigecycline and Tetracycline, Linezoli, Rifampicin, Fusidic Acid, Colistin, Chloramphenicol, Nitrofurantoin, Fidaxomicin, Fosfomycin, Antimycobacterials, Antifungals and Antivirals
All these topics are covered in the book...Ready to buy your copy? Click here to buy your copy of "Microbiology Nuts & Bolts" Its updated and amazingly only slightly larger considering its got 1/3 more in it! (11cmx18cmx2.5cm).
