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P A R T 2
Chemotherapeutic agents
after treatment has ended. Metronidazole and tinidazole
combined with oral anticoagulants can lead to increased
bleeding; people should be monitored closely and dose
adjustments made to the anticoagulant during therapy
and for up to 8 days after stopping therapy. Psychotic
reactions have been reported when tinidazole or metro-
nidazole is combined with disulfiram; this combination
should be avoided, and 2 weeks should elapse between
tinidazole therapy and the starting of disulfiram.
Increased bone marrow suppression may occur if
antifolate drugs (methotrexate, sulfonamides, etc.) are
combined with pyrimethamine; discontinue pyrimeth-
amine if signs of folate deficiency develop (diarrhoea,
fatigue, weight loss, anaemia).
Care considerations for
people receiving antiprotozoal agents
Assessment: History and examination
■
■
Assess for contraindications and cautions: history
of allergy to any of the antiprotozoals
to prevent
hypersensitivity reactions
; liver dysfunction
that
might interfere with metabolism and excretion of
the drug or be exacerbated by the drug
; pregnancy,
which is a contraindication
, and breastfeeding
because these drugs could enter the breast milk
and be toxic to the infant
; CNS disease
that could
be exacerbated by the drug
; and candidiasis
that
could become severe as a result of the effects of
these drugs on the normal flora
.
■
■
Perform a physical assessment
to establish baseline
data for determining the effectiveness of the
drug and the occurrence of any adverse effects
associated with drug therapy
.
■
■
Evaluate the CNS
to check reflexes and muscle
strength to identify the need for cautious drug use
and to evaluate changes that occur as a result of
drug therapy
.
■
■
Examine the skin and mucous membranes to check
for lesions, colour, temperature and texture
to
monitor for adverse effects and superinfections
.
■
■
Evaluate liver function, including liver function
tests,
to determine the appropriateness of therapy
and to monitor for toxicity
.
■
■
Obtain cultures
to determine the exact protozoal
species causing the disease
.
Implementation with rationale
■
■
Arrange for appropriate culture and sensitivity
tests before beginning therapy
to ensure proper
drug for susceptible organisms
. Treatment may
begin before test results are known.
■
■
Administer a complete course of the drug
to get the
full beneficial effects
. Use combination therapy as
indicated.
■
■
Monitor hepatic function before and periodically
during treatment
to arrange to effectively stop the
drug if signs of failure or worsening liver function
occur
.
■
■
Provide comfort and safety measures if CNS
effects occur, such as side rails and assistance with
ambulation if dizziness and weakness are present,
to prevent injury to the person
.
■
■
Provide oral hygiene and ready access to bathroom
facilities as needed
to cope with GI effects
.
■
■
Arrange for the treatment of superinfections as
appropriate
to prevent severe infections
.
■
■
Provide small, frequent, nutritious meals if
GI upset is severe
to ensure proper nutrition
.
Monitor nutritional status and arrange a dietary
consultation as needed. Taking the drug with food
may also decrease GI upset.
■
■
Instruct the person about the appropriate dosage
regimen
to enhance knowledge about drug therapy
and to promote compliance
.
■
■
Provide the following teaching:
–– Take safety precautions, including changing
position slowly and avoiding driving and
hazardous tasks, if CNS effects occur.
–– Take the drug with meals and try small, frequent
meals if GI upset is a problem.
–– Follow drug dosing guidelines carefully.
–– Report severe GI problems and interference with
nutrition; fever and chills, which may indicate
the presence of a superinfection; and dizziness,
unusual fatigue or weakness, which may indicate
CNS effects.
Evaluation
■
■
Monitor response to the drug (resolution of
infection and negative cultures for parasite).
■
■
Monitor for adverse effects (orientation and
affect, nutritional state, skin colour and
lesions, hepatic function and occurrence of
superinfections).
■
■
Evaluate the effectiveness of the teaching plan
(person can name the drug, dosage, possible
adverse effects to watch for and specific measures
to help avoid adverse effects).
■
■
Monitor the effectiveness of comfort and safety
measures and compliance with the regimen.
See Critical thinking scenario for additional
information related to coping with amoebiasis and
the use of metronidazole.
