C H A P T E R 9
Antibiotics
99
Clinically important drug–drug interactions
Consider an alternative antibiotic treatment if a person
is on sodium valproate. Combination of these drugs can
cause serum valproic acid levels to fall and increase the
risk of seizures. Avoid concurrent use of imipenem with
ganciclovir because this combination may also cause
seizures.
KEY POINTS
■■
Carbapenems are used to treat serious infections
caused by a wide range of bacteria.
■■
Monitor for GI effects, serious diarrhoea, dizziness
and superinfections.
CEPHALOSPORINS
The cephalosporins (Table 9.3) were first introduced in
the 1960s. These drugs are similar to the penicillins
in structure and in activity. Over time, four generations
of cephalosporins have been introduced, each group
with its own spectrum of activity.
KEY POINTS
Care considerations for
people receiving carbapenems
Assessment: History and examination
■
■
Assess for
possible contraindications or cautions
:
known allergy to any carbapenem or beta-lactam
(obtain specific information about the nature and
occurrence of allergic reactions); history of renal
disease; history of seizures and current pregnancy
or breastfeeding status.
■
■
Perform physical assessment
to establish baseline
data for assessing the effectiveness of the drug and
the occurrence of any adverse effects associated
with drug therapy.
■
■
Perform culture and sensitivity tests at the site of
infection.
■
■
Conduct orientation and reflex assessment
to
evaluate any CNS effects of the drug
.
■
■
Assess vital signs: respiratory rate and adventitious
sounds
to monitor for signs of infection or
hypersensitivity reactions
; temperature
to assess
for signs and symptoms of infection.
■
■
Perform renal function tests
to determine baseline
function of the kidneys and, possibly, the need to
adjust dose.
Implementation with rationale
■
■
Check culture and sensitivity reports
to ensure that
this is the drug of choice for this person.
■
■
Ensure that the person receives the full course
of the carbapenem as prescribed
to increase
effectiveness and decrease the risk for the
development of resistant strains of bacteria.
■
■
Monitor the site of infection and presenting signs
and symptoms (e.g. fever, lethargy) throughout
the course of drug therapy.
Failure of these signs
and symptoms to resolve may indicate the need to
reculture the site.
Arrange to continue drug therapy
for at least 2 days after all signs and symptoms
resolve
to decrease the development of resistant
strains of bacteria.
■
■
Monitor the person regularly for signs of
pseudomembranous colitis, severe diarrhoea
or superinfections
to effectively arrange for
discontinuation of drug or decreased dose, as
appropriate, if any of these toxicities occurs.
■
■
Provide safety measures
to protect the person
if CNS effects, such as confusion, dizziness or
seizures, occur.
■
■
Provide small, frequent meals as tolerated
to relieve
GI discomfort. Also provide adequate fluids to
replace fluid lost with diarrhoea, if appropriate.
■
■
Ensure that the person is hydrated at all times
during drug therapy
to minimise renal toxicity
from drug exposure.
■
■
Instruct the person about the appropriate dosage
regimen and possible adverse effects
to enhance
knowledge about drug therapy and to promote
compliance.
■
■
Provide the following teaching:
–– Take safety precautions, such as changing
position slowly and avoiding driving and
hazardous tasks, if CNS effects occur.
–– Try to drink a lot of fluids and to maintain
nutrition (very important) even though nausea,
vomiting and diarrhoea may occur.
–– Report difficulty breathing, severe headache,
severe diarrhoea, fever and signs of infection.
Evaluation
■
■
Monitor person’s response to the drug (resolution
of bacterial infection).
■
■
Monitor for adverse effects (orientation and affect,
superinfections, GI toxicity, severe diarrhoea
effects).
■
■
Evaluate effectiveness of the teaching plan (person
can name drug, dosage, possible adverse effects
to watch for and specific measures to help avoid
adverse effects).
■
■
Monitor effectiveness of comfort and safety
measures and compliance with the therapeutic
regimen.
