Transcript Pharmacology and the Nursing Process, 4th ed. Lilley/Harrington

Chapter 27
Antilipemic Drugs
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Triglycerides and Cholesterol
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Two primary forms of lipids in the blood
Water-insoluble fats that must be bound to
apolipoproteins, specialized lipid-carrying
proteins
Lipoprotein is the combination of triglyceride or
cholesterol with apolipoprotein
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Lipoproteins
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Very-low-density lipoprotein (VLDL)
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Produced by the liver
Transports endogenous lipids to the cells
Low-density lipoprotein (LDL)
High-density lipoprotein (HDL)
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Responsible for “recycling” of cholesterol
Also known as “good cholesterol”
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Cholesterol and Coronary Heart
Disease (CHD)
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The risk of CHD in patients with cholesterol
levels of 300 mg/dL is three to four times greater
than that in patients with levels less than 200
mg/dL.
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Hyperlipidemias and Treatment
Guidelines
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Antilipemic drugs
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Drugs used to lower lipid levels
Used as an adjunct to diet therapy
Drug choice based on the specific lipid profile of
the patient (phenotyping)
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Hyperlipidemias Treatment and
Guidelines (cont’d)
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All reasonable nondrug means of controlling
blood cholesterol levels (e.g., diet, exercise)
should be tried for at least 6 months and found
to fail before drug therapy is considered
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Antilipemics
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HMG-CoA reductase inhibitors (HMGs, or
statins)
Bile acid sequestrants
B vitamin niacin (vitamin B3, nicotinic acid)
Fibric acid derivatives (fibrates)
Cholesterol absorption inhibitor (Zetia)
Combination drugs (Vytorin)
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Antilipemics:
HMG-CoA Reductase Inhibitors
(HMGs, or statins)
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Most potent LDL reducers
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pravastatin (Pravachol)
 simvastatin (Zocor)
 atorvastatin (Lipitor)
 fluvastatin (Lescol)
 rosuvastatin (Crestor)
 pitavastatin (Livalo)
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HMG-CoA Reductase Inhibitors:
Mechanism of Action
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Inhibit HMG-CoA reductase, which is used by
the liver to produce cholesterol
Lower the rate of cholesterol production
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HMG-CoA Reductase Inhibitors:
Indications
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First-line drug therapy for hypercholesterolemia
Treatment of types IIa and IIb hyperlipidemias
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Reduces LDL levels by 30% to 40%
 Increases HDL levels by 2% to 15%
 Reduces triglycerides by 10% to 30%
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HMG-CoA Reductase Inhibitors:
Adverse Effects
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Mild, transient GI disturbances
Rash
Headache
Myopathy (muscle pain), possibly leading to the
serious condition rhabdomyolysis
Elevations in liver enzymes or liver disease
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HMG-CoA Reductase Inhibitors:
Interactions
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Oral anticoagulants
Drugs metabolized by CYP3A4
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erythromycin
 Azole antifungals
 verapamil
 diltiazem
 HIV protease inhibitors
 amiodarone
 Grapefruit juice
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Classroom Response Question
A patient with a new prescription for a HMGCoA (statin) drug is instructed to take the
medication with the evening meal or at bedtime.
The patient asks why it must be taken at this
time of day. The reason is:
A. The medication is better absorbed at this time.
B. This timeframe correlates better with the natural
diurnal rhythm of cholesterol production.
C. There will be fewer adverse effects if taken at night
instead of with the morning meal.
D. This timing reduces the incidence of myopathy.
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Bile Acid Sequestrants
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cholestyramine (Questran)
colestipol (Colestid)
colesevelam (Welchol)
Also called bile acid–binding resins and
ion-exchange resins
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Bile Acid Sequestrants: Mechanism
of Action
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Prevent resorption of bile acids from small
intestine
Bile acids are necessary for absorption
of cholesterol
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Bile Acid Sequestrants: Indications
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Type II hyperlipoproteinemia
Relief of pruritus associated with partial biliary
obstruction (cholestyramine)
May be used along with statins
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Bile Acid Sequestrants:
Adverse Effects
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Constipation
Heartburn, nausea, belching, bloating
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These adverse effects tend to disappear over
time
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Niacin (Nicotinic Acid)
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Vitamin B3
Lipid-lowering properties require much higher
doses than when used as a vitamin
Effective, inexpensive, often used in combination
with other lipid-lowering drugs
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Niacin: Mechanism of Action
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Thought to increase activity of lipase, which
breaks down lipids
Reduces the metabolism or catabolism of
cholesterol and triglycerides
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Niacin: Indications
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Effective in lowering triglyceride, total serum
cholesterol, and LDL levels
Increases HDL levels
Effective in the treatment of types IIa, IIb, III, IV,
and V hyperlipidemias
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Niacin: Adverse Effects
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Flushing (caused by histamine release)
Pruritus
GI distress
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Classroom Response Question
A patient will be taking niacin as part of antilipemic therapy.
The best way to avoid problems with flushing or pruritus
would be to:
A. take the medication at bedtime.
B. take the medication with a small dose of a steroid.
C. take the medication with a full glass of water on an
empty stomach.
D. start with a low initial dose, and then increase it
gradually.
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Fibric Acid Derivatives
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Also known as fibrates
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gemfibrozil (Lopid)
fenofibrate (Tricor)
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Fibric Acid Derivatives: Mechanism
of Action
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Believed to work by activating lipase, which
breaks down cholesterol
Also suppress the release of free fatty acid from
adipose tissue, inhibit synthesis of triglycerides
in the liver, and increase secretion of cholesterol
in the bile
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Fibric Acid Derivatives: Indications
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Treatment of types III, IV, and V hyperlipidemias
The fibric acid derivatives gemfibrozil and
fenofibrate decrease the triglyceride level and
increase the HDL cholesterol level by as much
as 25%
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Fibric Acid Derivatives:
Adverse Effects
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Abdominal discomfort, diarrhea, nausea
Blurred vision, headache
Increased risk of gallstones
Prolonged prothrombin time
Liver studies may show increased enzyme levels
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Fibric Acid Derivatives:
Interactions
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Oral anticoagulants
Statins
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Risk for myositis, myalgias, and rhabdomyolysis is
increased
Laboratory test reactions
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Decreased hemoglobin level, hematocrit value, and
white blood cell count
Increased activated clotting time, lactate
dehydrogenase level, and bilirubin level
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Cholesterol Absorption Inhibitor
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ezetimibe (Zetia)
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Inhibits absorption of cholesterol and related sterols
from the small intestine
Results in reduced total cholesterol, LDL, and
triglyceride levels
Also increases HDL levels
Often combined with a statin drug
Clinical trials continue
• Currently recommended only when patients have not
responded to other therapy
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Herbal Product: Garlic
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Used as an antispasmodic, antihypertensive,
antiplatelet, lipid reducer
Adverse effects: dermatitis, vomiting, diarrhea,
flatulence, antiplatelet activity
Possible interactions with warfarin, diazepam
May enhance bleeding when taken with NSAIDs
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Classroom Response Question
A patient wants to take garlic tablets to improve his
cholesterol levels. Which condition would be a
contraindication?
A. Hypertension
B. Bowel obstruction
C. Sinus infection
D. Scheduled surgery
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Herbal Product: Flax
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Both the seed and oil of the plant are used
Uses: atherosclerosis, hypercholesterolemia, GI
distress, menopausal symptoms
May cause diarrhea and allergic reactions
Possible interactions: antidiabetic drugs,
anticoagulant drugs
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Herbal Product: Omega-3
Fatty Acids
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Fish oil products
Used to reduce cholesterol
May cause rash, belching, allergic reactions
Potential interactions with anticoagulant drugs
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Nursing Implications
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Before beginning therapy, obtain a thorough
health and medication history
Assess dietary patterns, exercise level, weight,
height, vital signs, tobacco and alcohol use,
family history
Assess for contraindications, conditions that
require cautious use, and drug interactions
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Classroom Response Question
Which patient would benefit from administration of
simvastatin (Zocor) 80 mg?
A. A patient newly diagnosed with hyperlipidemia
B. A patient with muscle aches who was taking another
antilipidemic drug
C. A patient who is taking verapamil
D. A patient who has already been taking simvastatin
(Zocor) for 12 months with no evidence of myopathy
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Nursing Implications (cont’d)
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Contraindications include biliary obstruction,
liver dysfunction, active liver disease
Obtain baseline liver function studies
Patients on long-term therapy may need
supplemental fat-soluble vitamins (A, D, K)
Refer to guidelines regarding administration
times and meals
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Nursing Implications (cont’d)
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Counsel patient concerning diet and nutrition on
an ongoing basis
Instruct patient on proper procedure for taking
the medications
Powder forms must be taken with a liquid, mixed
thoroughly but not stirred, and never taken dry
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Nursing Implications (cont’d)
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Other medications should be taken 1 hour
before or 4 to 6 hours after meals to avoid
interference with absorption
To minimize adverse effects of niacin, start on
low initial dose and gradually increase it, and
take with meals
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Classroom Response Question
Before administering niacin, it is most important for
the nurse to assess the patient for
A. allergy to erythromycin.
B. gout.
C. coronary artery disease.
D. hypothyroidism.
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Nursing Implications (cont’d)
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Small doses of aspirin or NSAIDs may be taken
30 minutes before niacin to minimize cutaneous
flushing
Provide teaching regarding use of NSAIDs and
aspirin
Inform patients that these drugs may take
several weeks to show effectiveness
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Nursing Implications (cont’d)
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Instruct patients to report persistent GI upset,
constipation, abnormal or unusual bleeding, and
yellow discoloration of the skin
Monitor for adverse effects, including increased
liver enzyme studies
Monitor for therapeutic effects
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Reduced cholesterol and triglyceride levels
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