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P A R T 2
Chemotherapeutic agents
CHAPTER SUMMARY
■■
Anti-infectives are drugs designed to act on foreign
organisms that have invaded and infected the human
host with selective toxicity, which means that they
affect biological systems or structures found in the
invading organisms but not in the host.
■■
Anti-infectives include antibiotics, antivirals,
antifungals, antiprotozoals and anthelmintic agents.
■■
The goal of anti-infective therapy is interference with
the normal function of invading organisms to prevent
them from reproducing and promotion of cell death
without negative effects on the host cells. The infection
should be eradicated with the least toxicity to the host
and the least likelihood for development of resistance.
■■
Anti-infectives can work by altering the cell
membrane of the pathogen, by interfering with
protein synthesis or by interfering with the ability of
the pathogen to obtain needed nutrients.
■■
Anti-infectives also work to kill invading organisms
or to prevent them from reproducing, thus depleting
the size of the invasion to one that can be dealt with
by the human immune system.
■■
Pathogens can develop resistance to the effects
of anti-infectives over time when (1) mutant
organisms that do not respond to the anti-infective
become the majority of the pathogen population
or (2) the pathogen develops enzymes to block
the anti-infectives or alternative routes to obtain
nutrients or maintain the cell membrane.
■■
An important aspect of clinical care involving
anti-infective agents is preventing or delaying the
development of resistance. This can be done by
ensuring that the particular anti-infective agent is the
drug of choice for the specific pathogen involved and
that it is given in high enough doses for sufficiently
long periods to rid the body of the pathogen.
■■
Culture and sensitivity testing of a suspected
infection ensures that the correct drug is being
used to treat the infection effectively. Culture and
sensitivity testing should be performed before an
anti-infective agent is prescribed.
■■
Anti-infectives can have several adverse effects on
the human host, including renal toxicity, multiple GI
effects, neurotoxicity, hypersensitivity reactions and
superinfections.
■■
Some anti-infectives are used as a means of
prophylaxis when people expect to be in situations
that will expose them to a known pathogen, such as
travel to an area where malaria is endemic, or oral or
invasive GI surgery in a person who is susceptible to
subacute bacterial endocarditis.
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ONLINE RESOURCES
An extensive range of additional resources to enhance teaching
and learning and to facilitate understanding of this chapter may
be found online at the text’s accompanying website, located on
thePoint at
These include Watch and
Learn videos, Concepts in Action animations, journal articles,
review questions, case studies, discussion topics and quizzes.
WEB LINKS
Healthcare providers and students may want to consult
the following Internet sources:
content/cda-cdi3303e.htm
Department of Health and Ageing. Tuberculosis in
Australia.
/
campaigns-events/antibiotic-resistance-fighter
National Prescribing Service. Antibiotic Resistance.
World Health Organization. Antimicrobial Resistance.
BIBLIOGRAPHY
Bassler, B. & Winans, S. C. (2008).
Chemical Communication
Among Bacteria.
Hoboken, New Jersey: John Wiley & Sons.
Farrell, M. & Dempsey, J. (2014).
Smeltzer & Bare’s Textbook
of Medical-Surgical Nursing
(3rd edn). Sydney: Lippincott,
Williams & Wilkins.
Gillespie, E., Rodrigues, A., Wright, L., Williams, N. & Stuart, R. L.
(2013). Improving antibiotic stewardship by involving nurses.
American Journal of Infection Control, 41(4),
365–367.
McKenna, L. (2012).
Pharmacology Made Incredibly Easy
(1st Australian and New Zealand edn). Sydney: Lippincott
Williams & Wilkins.
McKenna, L. & Mirkov, S. (2014).
McKenna’s Drug handbook for
Nursing and Midwifery
(7th edn). Sydney: Lippincott Williams
& Wilkins.
McKenzie, D., Rawlins, M. & Del Mar, C. (2013). Antimicrobial
stewardship: What’s it all about?
Australian Prescriber, 36(4)
,
116–120.
Porth, C. M. (2011).
Essentials of Pathophysiology: Concepts
of Altered Health States
(3rd edn). Philadelphia: Lippincott
Williams & Wilkins.
Porth, C. M. (2009).
Pathophysiology: Concepts of Altered Health
States
(8th edn). Philadelphia: Lippincott Williams & Wilkins.
RHD Australia, National Heart Foundation of Australia
and the Cardiac Society of Australia and New Zealand.
(2012).
Australian Guideline for Prevention, Diagnosis and
Management of Acute Rheumatic Fever and Rheumatic Heart
Disease
(2nd edn).
guideline0.pdf.
Turnidge, J. (2010). Multiresistant organisms at the front line.
Australian Prescriber, 33(3)
, 68–71.
World Health Organisation. (2013).
Antimicrobial resistance. Fact
Sheet No. 194.
.
