Salicylic acid
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Transcript Salicylic acid
Chapter 44
1
Antiinflammatory and Antigout Drugs
Fall 2012
NSAIDs
non-steroidal anti-inflammatory drugs
Large and chemically diverse group of
drugs with the following properties:
Analgesic
Antiinflammatory
Antipyretic
Antirheumatic
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NSAIDs: Mechanism of Action
Activation of the arachidonic acid
pathway causes:
Pain
Headache
Fever
Inflammation
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NSAIDs: Mechanism of Action (cont’d)
Analgesia—treatment of headaches,
mild to moderate pain, and inflammation
Block the chemical activity of either or both
COX enzymes (prostaglandin [PG] pathway)
and lipoxygenase (LT pathway)
Result in limiting the undesirable
inflammatory effect of PGs
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NSAIDs: Mechanism of Action (cont’d)
Antipyretic—reduces fever
Inhibits prostaglandin within the area of the
brain that controls temperature
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Chemical Categories of NSAIDs
Salicylates
Acetic acid derivatives
Cyclooxygenase-2 (COX-2)
inhibitors
Enolic acid derivatives
Propionic acid derivatives
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NSAIDs: Salicylates
Salicylates also have antiplatelet
activity
Inhibit platelet aggregation
Examples: aspirin, diflunisal (Dolobid),
others
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NSAIDs: Acetic Acids
indomethacin (Indocin)
ketorolac (Toradol)
diclofenac sodium (Voltaren)
sulindac (Clinoril)
tolmetin (Tolectin)
etodolac (Lodine)
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NSAIDs: COX-2 Inhibitor
celecoxib (Celebrex)
First and only remaining COX-2 inhibitor
Indicated for osteoarthritis, rheumatoid
arthritis, acute pain symptoms, ankylosing
spondylitis, and primary dysmenorrhea
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NSAIDs: Enolic Acid Derivatives
piroxicam (Feldene)
meloxicam (Mobic)
namumetone (Relafen)
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NSAIDs: Propionic Acids
fenoprofen (Nalfon)
flurbiprofen (Ansaid)
ibuprofen (Motrin, Advil, others)
ketoprofen (Orudis KT)
naproxen (Naprosyn, Aleve)
oxaprozin (Daypro)
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NSAIDs: Indications
Analgesia (mild to moderate)
Antigout effects
Antiinflammatory effects
Antipyretic effects
Relief of vascular headache
Platelet inhibition (aspirin)
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NSAIDs: Indications (cont’d)
Relief of mild to moderate pain
Acute gout
Various bone, joint, and muscle
pain
Osteoarthritis
Rheumatoid arthritis
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NSAIDs: Indications (cont’d)
Rheumatoid arthritis
Dysmenorrhea
Fever
Many other conditions
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Salicylates: Indications
Salicylic acid (aspirin)
More potent effect on platelet aggregation and
thermal regulatory center in the brain
Analgesic
Antipyretic
Antiinflammatory
Antithrombotic effect: used in the treatment of MI
and other thromboembolic disorders
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Antigout Drugs: Indications
Gout: condition that results from
inappropriate uric acid metabolism
Underexcretion of uric acid
Overproduction of uric acid
Uric acid crystals are deposited in tissues
and joints, resulting in pain
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Antigout Drugs: Indications (cont’d)
allopurinol (Zyloprim)
Used to reduce production of uric acid
colchicine
Reduces inflammatory response to the
deposits of urate crystals in joint tissue
probenecid (Benemid), sulfinpyrazone
(Anturane)
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Increase excretion of uric acid in the urine
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NSAIDs: Adverse Effects
Gastrointestinal
Dyspepsia, heartburn, epigastric
distress, nausea
GI bleeding*
Mucosal lesions* (erosions or ulcerations)
* Misoprostol (Cytotec) can be used to reduce these
dangerous effects.
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NSAIDs: Adverse Effects (cont’d)
Renal
Reductions in creatinine clearance
Acute tubular necrosis with renal
failure
Cardiovascular
Noncardiogenic pulmonary edema
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NSAIDs: Salicylate Toxicity
Adults: tinnitus and hearing loss
Children: hyperventilation and CNS
effects
Metabolic acidosis and respiratory
alkalosis may be present
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NSAIDs: Interactions
Serious interactions can occur when given with:
Anticoagulants
Aspirin
Corticosteroids and other ulcerogenic drugs
Protein bound drugs
Diuretics and ACE Inhibitors
Others
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Herbal Products:
Glucosamine and Chondroitin
Used to treat the pain of osteoarthritis
Adverse effects
GI discomfort
Drowsiness, headache, skin reactions
(glucosamine)
Drug interactions
Enhance effects of warfarin
May increase insulin resistance
(glucosamine)
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NSAIDs: Nursing Implications
Before beginning therapy, assess for
conditions that may be contraindications to
therapy, especially:
GI lesions or peptic ulcer disease
Bleeding disorders
Assess for conditions that require cautious use
Perform lab studies as indicated (cardiac,
renal, and liver function studies, CBC, platelet
count)
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Nursing Implications
Do NOT give salicylates to children and
teenagers because of the risk of Reye’s
syndrome
Because these drugs generally cause GI
distress, they are often better tolerated if taken
with food, milk, or an antacid to avoid irritation
Explain to patients that therapeutic effects may
not be seen for 3 to 4 weeks
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Nursing Implications (cont’d)
Educate patients about the various adverse
effects of NSAIDs, and inform them to notify
their physician if these effects become severe
or if bleeding or GI pain occurs
Inform patients to watch closely for the
occurrence of any unusual bleeding, such as
in the stool
Advise patients that enteric-coated tablets
should not be crushed or chewed
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Nursing Implications (cont’d)
Monitor for therapeutic effects, which vary
according to the condition being treated
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Decrease in swelling, pain, stiffness,
and tenderness of a joint or muscle area
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