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P A R T 8
Drugs acting on the cardiovascular system
Adverse effects
The most common adverse effects associated with eze-
timibe are mild abdominal pain and diarrhoea. It is
not associated with the bloating and flatulence that
occurs with the bile acid sequestrants and another class
of lipid-lowering drugs called fibrates. Other adverse
effects that have been reported include headache, dizzi
ness, fatigue, upper respiratory tract infection (URI),
back pain and muscle aches and pains.
Clinically important drug–drug interactions
The risk of elevated serum levels of ezetimibe increases if
it is given with cholestyramine, fenofibrate, gemfibrozil
or antacids. If these drugs are used in combination, eze-
timibe should be taken at least 2 hours before or 4 hours
after the other drugs.
The risk of toxicity also increases if ezetimibe is
combined with cyclosporin. If this combination cannot
be avoided, the person should be monitored very closely.
If ezetimibe is combined with any fibrate, the risk of
cholethiasis increases. The person should be monitored
closely. Warfarin levels increase in a person who is also
taking ezetimibe; if this combination is used, the person
should be monitored very closely.
Prototype summary: Ezetimibe
Indications:
Adjunct to diet and exercise to lower
serum cholesterol levels; in combination with
atorvastatin or simvastatin for the treatment of
homozygous familial hypercholesterolaemia;
with diet for the treatment of homozygous
sitosterolaemia to lower sitosterol and campesterol
levels.
Actions:
Works in the brush border of the small
intestine to inhibit the absorption of cholesterol.
Pharmacokinetics:
Route
Onset
Peak
Oral
Moderate
4–12 hours
T
1/2
:
22 hours; metabolised in the liver and small
intestine and excreted in faeces and urine.
Adverse effects:
Headache, dizziness, abdominal pain,
diarrhoea, URI, back pain, myalgia, arthralgia.
Care for people receiving
cholesterol absorption inhibitors
Assessment: History and examination
■
■
Assess for contraindications or cautions: any known
allergies to any component of the drug
to avoid
hypersensitivity reactions
; liver dysfunction or
advanced age
because the processing of the drug
may differ from the norm
; current status of
pregnancy or breastfeeding
because the possible
effects on the fetus or neonate are not know
n.
■
■
Perform a physical assessment to establish a
baseline before beginning therapy and during
therapy
to determine its effectiveness and evaluate
for any potential adverse effects.
■
■
Monitor orientation and reflexes
to detect changes
in CNS function, such as dizziness, that could
require safety measures.
■
■
Monitor respirations and auscultate lungs for
evidence of adventitious sounds to monitor
changes in cardiac output.
■
■
Inspect the abdomen for distension and auscultate
bowel sounds
for changes in gastrointestinal
motility.
■
■
Assess bowel elimination patterns, including
frequency of stool passage and stool characteristics,
to identify possible changes that could require
intervention.
■
■
Monitor the results of laboratory tests, including
serum cholesterol and lipid levels,
to evaluate the
effectiveness of drug therapy
, and liver function
studies
to monitor for toxic effects.
Implementation with rationale
■
■
Monitor serum cholesterol, triglyceride and LDL
levels before and periodically during therapy
to
evaluate the effectiveness of this drug.
■
■
Monitor liver function tests before and periodically
during therapy
to detect possible liver damage.
■
■
Ensure that the person has attempted a cholesterol-
lowering diet and exercise program for at least
several months before beginning therapy
to ensure
the need for drug therapy.
■
■
Encourage the person to make the lifestyle changes
necessary
to decrease the risk of CAD and to
increase the effectiveness of drug therapy.
■
■
Suggest the use of barrier contraceptives for women
of childbearing age if the drug is being used in
combination with a statin
because there is a risk of
severe fetal abnormalities if these drugs are taken
during pregnancy.
■
■
Provide comfort measures
to help the person
tolerate drug effects.
These include readily available
access to bathroom facilities
to help with episodes
of diarrhoea
; safety precautions
to protect the
individual if dizziness is an issue
; and analgesics
for headache and muscle aches if appropriate.
■
■
Offer support and encouragement
to help the
person deal with the diagnosis, needed lifestyle
changes and the drug regimen.
