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P A R T 2
Chemotherapeutic agents
KEY POINTS
■■
Hepatitis B and C are serious-to-potentially fatal
viral infections of the liver spread by blood or blood
products, sexual contact, or contaminated needles or
instruments. Hepatitis B has a higher mortality than
other types of hepatitis.
■■
Prevention of infection through use of hepatitis B
vaccines and avoiding exposure is essential in
stopping the spread of this disease.
■■
Hepatitis B and C used to be treated only with
interferons and rest. Entecavir, adefovir and
telbivudine are antivirals now available for the
treatment of hepatitis B. Boceprevir and telaprevir
are used for the treatment of hepatitis C.
LOCALLY ACTIVE ANTIVIRAL AGENTS
Some antiviral agents are given locally to treat local
viral infections. These agents include ganciclovir (
Vitra-
sert
) and imiquimod (
Aldara
).
Therapeutic actions and indications
These antiviral agents act on viruses by interfering with
normal viral replication and metabolic processes. They
are indicated for specific, local viral infections (see
Table 10.5).
KEY POINTS
Care considerations for
people receiving anti-hepatitis B or C agents
Assessment: history and examination
■
■
Assess for
contraindications or cautions
: any
history of allergy to any of the agents
to avoid
hypersensitivity reactions
; renal dysfunction,
which could be exacerbated by the nephrotoxic
effects of these drugs
; severe liver impairment,
which could affect the metabolism and exacerbate
the liver toxicity of these drugs
; and pregnancy and
breastfeeding
because the potential effects of these
drugs on the fetus or baby are not known.
■
■
Perform a physical assessment
to establish baseline
data for assessing the effectiveness of these
drugs and the occurrence of any adverse effects
associated with drug toxicity.
■
■
Assess body temperature
to monitor underlying
disease.
■
■
Assess level of orientation and reflexes
to assess
for CNS changes.
■
■
Evaluate renal and liver function tests
to monitor
for developing toxicity and to determine drug
effectiveness.
Implementation with rationale
■
■
Monitor renal and hepatic function prior to and
periodically during therapy
to detect renal or
hepatic function changes and determine the need
for possible dose reduction or institute treatment
as needed.
■
■
Withdraw the drug and monitor the person if they
develop signs of lactic acidosis or hepatotoxicity
because these adverse effects can be life
threatening.
■
■
Caution person to not stop the medication and to
take it continually
because acute exacerbation of
hepatitis B or C can occur when the drug is stopped.
■
■
Advise women of childbearing age to use barrier
contraceptives
because the potential adverse effects
of this drug on the fetus are not known.
■
■
Advise women who are breastfeeding to find
another method of feeding the baby while using
the drug
because the potential toxic effects on the
baby are not known.
■
■
Advise people that these drugs do not cure the
disease and there is still a risk of transferring the
disease,
so the person should continue to take
appropriate steps to prevent transmission of
hepatitis B or C.
■
■
Instruct the person about the drug prescribed
to enhance knowledge about drug therapy and to
promote compliance.
■
■
Provide the following teaching:
–– Have regular blood tests and medical follow-up.
–– Take precautions to maintain a constant supply
of the drug, because it must be taken continually,
and avoid missing doses.
–– Realise that GI upset, with nausea and diarrhoea,
is common with these drugs.
–– Report severe weakness, muscle pain,
palpitations, yellowing of the eyes or skin and
trouble breathing.
Evaluation
■
■
Monitor response to the drug (decreased viral load
of hepatitis B or C).
■
■
Monitor for adverse effects (liver or renal
dysfunction, headache, nausea, diarrhoea).
■
■
Evaluate the effectiveness of the teaching plan
(person can name the drug, dosage, possible
adverse effects to watch for and specific measures
to avoid adverse effects).
■
■
Monitor the effectiveness of comfort and safety
measures and compliance with the drug regimen.
