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3990 veraflox bacterial cell visual guide v20.indd

BACK TO BASICS
MECHANISM OF ACTION OF THE
MAJOR ANTIBIOTIC GROUPS
CELL WALL SYNTHESIS INHIBITORS
In a recent survey1, vets identified that
remembering the intricacies of every different
Penicillins
antibiotic could sometimes be a challenge.
• Bactericidal • Bactericidal This guide is intended as an antibiotic refresher,
• Time-dependent killing • Time-dependent killing and details a number of key factors to consider
• Examples include: • Four generations with varying when prescribing an antibiotic. 81% of vets
Amoxicillin, Amoxicillin- antibacterial spectrums Clavulanate, Ampicillin • Examples include: surveyed identified that antibiotic resistance is a
Cefalexin (first generation) topic that concerns them; this guide includes a
Cefovecin (third generation) section on fluoroquinolone resistance, and looks
at ways that this can be minimised.
NUCLEIC ACID SYNTHESIS INHIBITORS
Sulphonamides and
• Inhibit bacterial DNA synthesis Potentiated Sulphonamides
• Bactericidal • Block folic acid synthesis • Concentration-dependent • Sulphonamides are bacteriostatic, become • Examples include: bactericidal when potentiated Second generation FQs: • Examples include: Enrofloxacin, Marbofloxacin, Orbifloxacin Third generation FQs: Pradofloxacin CELL MEMBRANE FUNCTION INHIBITORS
Polymyxins
• Generally used in topical medications
• Examples include: Polymyxin B
PROTEIN SYNTHESIS INHIBITORS
• Bacteriostatic • Bactericidal • Examples include: • Concentration- Clindamycin, Lincomycin dependent killing • Examples include: * Not licensed for veterinary use
Gentamicin and Framycetin (these are licensed for topical use only) • Bacteriostatic Metronidazole is not licensed for
• Examples include: sole use, but is licensed for oral use in
Macrolides
combination with spiramycin.
• Bacteriostatic ‡ Oxytetracycline is not licensed for
• Examples include: use in cats.
• Bacteriostatic Spiramycin, Erythromycin*, RESPONSIBLE CHOICE FOR SEVERE INFECTIONS
Refer to appropriate data sheets for
specific indications and warnings.
BACTERICIDAL VS.
TIME DEPENDENT VS. CONCENTRATION
DEPENDENT BACTERIAL KILLING
Bacteriostatic antibiotics inhibit the growth of bacteria, With time dependent antibiotics (such as penicillins and whereas bactericidal agents cause death of the cephalosporins), serum levels of the antibiotic should bacteria. Bactericidal agents are sometimes preferable exceed the MIC for as long as possible during each 24 hour in infections where the immune status of the patient period; these agents usually require multiple daily doses to is compromised.
achieve this. Concentration dependent antibiotics (such as Distinction between these two groups is not always fluoroquinolones and aminoglycosides) rely on high peak clear cut however, and other factors are usually more concentrations to achieve bacterial killing; dosing schedules important in determining antibiotic choice.
are usually once daily.
FACTORS TO CONSIDER WHEN PRESCRIBING AN ANTIBIOTIC
Is an antibiotic definitely indicated?
What is the likely bacterial species present?
Use cytology and culture where appropriate. Culture is especially important when empirical therapy has been ineffective, and/or long antibiotic courses are required. Consider the method of antimicrobial delivery:
would topical agents be effective?
Take into account the site of infection
when analysing culture and sensitivity results
Susceptibility results are generally based on antimicrobial concentrations achievable in the bloodstream, and do not take tissue levels into account. Does the antibiotic penetrate the infected tissue and reach adequate concentrations? Are there any potential toxicities or
contra-indications associated with the antibiotic
that need to be considered?
Consider the likelihood that an antibiotic
may contribute to resistance
Different members of the same antimicrobial class may
carry different risks of selecting for resistance*
Compliance
Is the owner likely to be able to give the treatment prescribed? DO YOU FEEL LIKE YOU KNOW ENOUGH ABOUT ANTIBIOTICS?
Why not test your knowledge and get CPD hours at the same time, using the Antibiotics Back to Basics assessment online resource at www.veraflox.co.uk
ANTIBIOTIC ACRONYM BUSTER
THE MUTANT
Minimum Inhibitory
Mutant Prevention
The Mutant Selection Window
Concentration (MPC)
This is the zone between the MIC The lowest concentration of The lowest concentration of and MPC. If an antibiotic is able to an antimicrobial that will inhibit an antimicrobial that will kill exceed MIC levels in the body but the visible growth of a bacterial not only susceptible bacteria, does not reach MPC levels, it is in isolate after incubation for but also the least susceptible the Mutant Selection Window. This 18 – 24 hours.
bacteria present in high is the danger zone - the antibiotic is killing susceptible bacteria but leaving first-stage mutants behind.
What is a first-step mutant?
Mutant Selection Window (MSW)
In large bacterial populations, spontaneous mutations can occur, Blondeau et al, J. Chemo, 2004 that render the "mutant" bacteria harder to kill. In the case of fluoroquinolones, resistance occurs in a step-wise manner; and bacteria that undergo these spontaneous mutations are referred to as first-step mutants. If first-step mutants are not killed during therapy, they may proliferate and mutate further.
Fluoroquinolones that achieve levels above the MPC are less likely
Serum or tissue drug concentration
to leave first-step mutant bacteria behind during therapy.3-5
FLUOROQUINOLONE MPC PROFILE
Cmax: maximum amount of antibiotic
achieved in the serum of the animal with * Compared to other standard dosing.
fluoroquinolones, Veraflox® is the least likely to select The bars represent the MPC value for each antibiotic (i.e. the amount of antibiotic needed to kill both susceptible and first-step mutant bacteria) • By achieving drug concentrations that exceed the MPC, the potential Where the bar turns red beyond the Cmax, this indicates that the amount for selection of resistant of antibiotic needed to reach MPC bacteria is reduced.3-5 (and thus kill first-step mutants) is not achieved during normal dosing with • When a fluoroquinolone is the FQ specified. indicated, choosing the one that is the least likely to leave first-step mutants behind is the best way to help minimise the escalation of Comparative MPC values
of veterinary fluoroquinolones
against Staphylococcus sp.
in relation to serum drug levels
reached in dogs2
• Ensure that the owner can administer the Bayer offer a range of resources to support medication - both dosing method and frequency the use of antibiotics in practice.
(demonstrate how to give medication if possible) • Advise clients on the importance of correct Visit www.animalhealthwebinars.bayer.co.uk treatment intervals (for example every twelve to source a number of cpd webinars, hours is more specific than twice daily; which including Joe Blondeau discussing the Mutant is crucial for the efficacy of some antibiotics) • Educate owner about the importance of Compliance an issue?
completing the course The following tools may be useful:
Client leaflets & reminder magnets
These leaflets detail the importance
of completing the whole antibiotic course,
ANTIBIOTIC REMINDERS
and offer a handy record, so your clients can keep track of when they need to give their pet the next dose.
App Reminders
The Jungle App now offers antibiotic
reminders for Veraflox®, Baytril
and Nisamox. All your clients need to
do is fill in the treatment, course length
and time of day for the first treatment
and the app will do the rest!
AVAILABLE ON APPLE iOS AND ANDROID!
YOUR BAYER REPRESENTATIVE FOR MORE INFORMATION Use Medicines Responsibly (www.noah.co.uk/responsible)
Veraflox® 15 mg tablets contain 15 mg pradofloxacin. Veraflox® 60 mg tablets contain 60 mg pradofloxacin. Veraflox® 120 mg tablets contain 120 mg pradofloxacin. Veraflox®
25 mg/ml oral suspension for cats contains 25 mg/ml pradofloxacin. Please refer to appropriate data sheet at noahcompendium.co.uk. Advice should be sought from the medicine
prescriber. Further information is available on request. ® Registered Trade Mark of Bayer AG. Bayer plc, Animal Health Division, Bayer House, Strawberry Hill, Newbury, Berkshire RG14
1JA Tel: 01635 563000 POM-V Bayer Ltd, Animal Health Division, The Atrium, Blackthorn Road, Dublin 18, Ireland Tel: 01 299 9313 POM EU/2/10/107/003 EU/2/10/107/007
EU/2/10/107/009 EU/2/10/107/013. CODE
References: 1.Survey of 456 practising UK vets conducted by surveymonkey in March 2014 2.Wetzstein HG. Comparative mutant prevention concentrations of pradofloxacin and other
veterinary fluoroquinolones indicate differing potentials in preventing selection of resistance. Antimicrob Agents Chemother. 2005;49(10):4166-4173. 3.Blondeau JM. Mutant Prevention
Concentration. In STAT - Steps to Antimicrobial Therapy. North American Compendiums Inc., Port Huron, MI, USA 2009: 67 - 98.4.Blondeau JM. New concepts in antimicrobial susceptibility
RESPONSIBLE CHOICE FOR SEVERE INFECTIONS
testing: the mutant prevention concentration and mutant selection window approach. Vet Dermatology 2009; 20: 383 - 396. 5.Mateus A, Brodbelt D, Stark K. Evidence-based use of antimicrobials in veterinary practice. In Practice 2011; 33: 194 - 202. 6.Heinen E. Comparative serum pharmacokinetics of the fluoroquinolones enrofloxacin, difloxacin, marbofloxacin and orbifloxacin in dogs after single oral administration. J Vet Pharmacol Therap 2002; 25: 1-5.

Source: http://www.veraflox.co.uk/static/documents/brochures/3990_Veraflox_Bacterial_Cell.pdf