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P A R T 2
Chemotherapeutic agents
headache and central nervous system (CNS) changes
occurring most frequently.
Clinically important drug–drug interactions
People who receive amphotericin B should not take
other nephrotoxic drugs such as nephrotoxic antibiotics
or antineoplastics, cyclosporin or corticosteroids unless
absolutely necessary
because of the increased risk of
severe renal toxicity.
Prototype summary: Fluconazole
Indications:
Treatment of oropharyngeal,
oesophageal and vaginal candidiasis; cryptococcal
meningitis; systemic fungal infections; prophylaxis
to decrease the incidence of candidiasis in bone
marrow transplants.
Actions:
Binds to sterols in the fungal cell membrane,
changing membrane permeability; fungicidal or
fungistatic, depending on the concentration of drug
and the organism.
Pharmacokinetics:
Route Onset
Peak
Duration
Oral
Slow
1–2 hours
2–4 days
IV Rapid
1 hour
2–4 days
T
1/2
:
30 hours; metabolised in the liver and excreted
in the urine.
Adverse effects:
Headache, nausea, vomiting,
diarrhoea, abdominal pain, rash.
Care considerations for
people receiving systemic antifungals
Assessment: History and examination
■
■
Assess the person for
contraindications or
cautions
: history of allergy to antifungals
to
prevent potential hypersensitivity reactions
;
history of liver or renal dysfunction
that might
interfere with metabolism and excretion of the
drug
; and pregnancy or breastfeeding
because of
potential adverse effects to the fetus or infant
.
■
■
Perform a physical assessment
to establish baseline
data for assessing the effectiveness of the drug and
the occurrence of any adverse effects associated
with drug therapy
; test orientation and reflexes
to evaluate any CNS effects
; and examine skin
for colour changes and lesions
to monitor for any
dermatological effects
.
■
■
Obtain a culture of the infected area
to make
an accurate determination of the type and
responsiveness of the fungus
.
■
■
Evaluate renal and hepatic function tests and full
blood count
to determine baseline function of
these organs and to assess possible toxicity during
drug therapy
.
Implementation with rationale
■
■
Arrange for appropriate culture and sensitivity
tests before beginning therapy
to ensure that the
appropriate drug is being used
. However, in some
cases, treatment can begin before test results are
known because of the seriousness of the systemic
infections.
■
■
Administer the entire course of the drug
to get
the full beneficial effects
; this may take as long as
6 months for some chronic infections.
■
■
Monitor IV sites
to ensure that phlebitis or
infiltration does not occur
. Treat appropriately and
restart IV at another site if phlebitis occurs.
■
■
Monitor renal and hepatic function before and
periodically during treatment to assess for possibly
dysfunction
and arrange to stop the drug if signs of
organ failure occur
.
■
■
Provide comfort and safety provisions if CNS effects
occur (e.g. side rails and assistance with ambulation
for dizziness and weakness, analgesics for headache,
antipyretics for fever and chills, temperature
regulation for fever)
to protect the person from injury
.
■
■
Provide small, frequent, nutritious meals if GI
upset is severe. Monitor nutritional status and
arrange a dietary consultation as needed
to ensure
nutritional status
. GI upset may be decreased by
taking an oral drug with food.
■
■
Instruct the person
to enhance knowledge about
drug therapy and to promote compliance
.
■
■
Provide the following teaching:
–– Follow the appropriate dosage regimen.
–– Take safety precautions, including changing
position slowly and avoiding driving and
hazardous tasks, if CNS effects occur.
–– Take an oral drug with meals and try small,
frequent meals if GI upset is a problem.
–– Report to a healthcare provider any of the
following: sore throat, unusual bruising and
bleeding or yellowing of the eyes or skin, all of
which could indicate hepatic toxicity; or severe
nausea and vomiting, which could interfere with
nutritional state and slow recovery.
Evaluation
■
■
Monitor person’s response to the drug (resolution
of fungal infection).
■
■
Monitor for adverse effects (orientation and affect,
nutritional state, skin colour and lesions, renal and
hepatic function).
