Guidelines for Prescribing, Authorising and Dispensing - Australian ...

7 Therapeutic need
The administration of any medication can produce a range of harmful effects,
including:
� selection or promotion of antimicrobial resistance;
� hypersensitivity reactions;
� direct tissue or organ toxicity,
� toxic interactions with other drugs;
� interference with the protective effect of normal host microflora;
� tissue necrosis at injection sites;
� impairment of host immune or defence mechanisms; and
� production of residues in animal products for human consumption.
When presented with a particular case, a veterinarian is required to establish the
therapeutic need for any treatment regimen.
There should be clinical justification and documentation for the therapeutic need.
This should include a record of clinical examination, any laboratory test results,
radiographs etc, and record of diagnosis and consideration of appropriate
therapies.
Prophylactic antimicrobial use in surgery
Prophylactic antimicrobial drugs in surgery are not indicated for routine, aseptic
surgery of less than 90 minutes duration where no pre-existing infection is present,
the gastrointestinal, female reproductive or respiratory systems have not been
invaded, and aseptic technique is maintained. However, the use of antibiotics in a
prophylactic manner may be justified in situations such as operative procedures in
the field, dental procedures with associated bleeding, patients with leucopoenia,
contaminated surgery, or where the consequences of sepsis would be potentially
irreversible, life-threatening or likely to cause prolonged pain or suffering.
For antibacterial chemoprophylaxis, drugs should be administered before the
procedure so that adequate concentrations are present in vivo at the time of
surgery - for best effect the drug must be present in the wound before
contamination occurs. The likely contaminating pathogens should be considered
when selecting the appropriate antibacterial drug to use prophylactically.
Antimicrobial prophylaxis is less effective if the contamination of the surgical site
includes certain particulate matter. Where contamination has been present for
three or more hours, benefits of antibiotics may be reduced.
8 Species knowledge
When prescribing, authorising and/or dispensing drugs it is the responsibility of a
veterinarian to ensure that they have adequate knowledge of the species involved.
Where this is not the case they should consider obtaining advice from a colleague
with the required knowledge or referring the client to a specialist or more
experienced colleague.
AVA Prescribing and dispensing guidelines
Version 1.0 February 2005
Updated 02/09/08
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