Chapter 74 - NSAIDs and Acetaminophen

Question 1

How do cyclooxygenase inhibitors work?

Answer 1

inhibit COX, the enzyme that converts arachidonic acid into prostanoids

Question 2

What does COX regulate?

Answer 2

-stomach: promote PGE2 and PGI2 synthesis that protect mucosa
-promote inflammation and sensitize receptors to pain
-stimulate platelet aggregation
-causes vasodilation via prostacyclin
-vasodilation in kidneys
-mediates fever and contributes to pain perception
-promotes uterine contractions

Question 3

What is the benefit of inhibiting COX-1?

Answer 3

protect against MI and stroke

Question 4

Drugs that inhibit COX-1 can cause:

Answer 4

-gastric ulcers
-bleeding
-renal impairment

Question 5

What are the beneficial effects of COX-2 inhibition?

Answer 5

-suppress inflammation
-alleviate pain and fever
-protect against colorectal cancer

Question 6

What are things that drugs that inhibit COX-2 can cause?

Answer 6

-renal impairment
-promotion of MI and stroke

Question 7

What are COX inhibitors used for?

Answer 7

-suppressing inflammation
-pain relief
-fever reduction

Question 8

NSAIDs are a class of __________

Answer 8

COX inhibitors

Question 9

What are some NSAIDs?

Answer 9

-aspirin (ASA)
-celecoxib
-ibuprofen (advil)
-naproxen
-diclofenac
-ketoprofen
-flurbiprofen
-indomethacin
-ketorolac
-menfenamic acid

Question 10

What are the classes of COX inhibitors?

Answer 10

-anti-inflammatory - NSAIDs
-not anti-inflammatory - acetaminophen (tylenol)

Question 11

1st Gen NSAIDs inhibit COX ___

Answer 11

1 and 2

Question 12

What are 1st gen NSAIDs used to treat?

Answer 12

-inflammatory disorders
-pain
-fever

Question 13

How does ASA act?

Answer 13

non-selectively inhibits COX

Question 14

Does ASA pass membranes?

Answer 14

yes all including fetal tissue and CNS

Question 15

What are the uses of ASA?

Answer 15

-analgesic
-antipyretic
-anti inflammatory
-suppresses platelet aggregation
-cancer prevention

Question 16

What are the adverse effects of ASA?

Answer 16

-GI effects
-bleeding
-renal impairment
-tinnitus
-sweating
-headache
-dizziness
-pregnancy - anemia, hemorrhage, prolong labour
-hypersensitivity

Question 17

What does ASA interact with?

Answer 17

-anticoagulants
-glucocorticoids
-alcohol
-ibuprofen
-ACEIs
-ARBs

Question 18

ASAs should not be used in people with…

Answer 18

-bleeding disorders
-peptic ulcer disease

Question 19

How are non-ASA 1st gen NSAIDs different:

Answer 19

-fewer Gi, renal, hemorrhagic effects
-have reversible inhibition
-don’t protect against MI and strok

Question 20

What are non-ASA 1st gen NSAIDs used for?

Answer 20

-rheumatoid arthritis
-osteoarthritis
-pain conditions

Question 21

What kind of drug is ibuprofen?

Answer 21

1st gen NSAID

Question 22

How does ibuprofen act?

Answer 22

COX inhibition and antiinflammatory, analgesic, antipyretic actions

Question 23

What is ibuprofen used for?

Answer 23

-fever
-mild to moderate pain
-arthritis

Question 24

What are the adverse effects of ibuprofen?

Answer 24

-GI upset
-risk of GI bleed
-confusion in elderly
-allergic rxn
-fluid retention

Question 25

What is a safety risk for 1st gen NSAIDs?

Answer 25

-risk of GI bleeding: esp with hx of ulcer, multiple NSAID use, anticoagulant, SSRI, steroid, > 60 yoa, hx of heart disease

Question 26

How do 2nd gen NSAIDs compare?

Answer 26

-just as effective -lower risk of GI side effects -can impair renal function -may cause HTN and edema -increased risk of MI and stroke -work mainly on COX 2

Question 27

What drug class is Celecoxib?

Answer 27

a 2nd gen COX 2 inhibitor

Question 28

Why is Celecoxib the last choice drug for pain?

Answer 28

CV effects

Question 29

What is celecoxib used for?

Answer 29

-osteoarthritis -rheumatoid arthritis -acute pain

Question 30

What are the adverse effects of celecoxib?

Answer 30

-dyspepsia -abdominal pain -sulfa allergy -CV events

Question 31

What is acetaminophen (tylenol) used for?

Answer 31

-analgesic -antipyretic -no anti inflammatory or antirheumatic action -not associated with Reye's syndrome

Question 32

How does acetaminophen act?

Answer 32

inhibits prostaglandin synthesis in CNS (not periphery)

Question 33

What does acetaminophen interact with?

Answer 33

ALCOHOL and warfarin

Question 34

How is acetaminophen metabolized?

Answer 34

-major pathway is conjugation to nontoxic metabolites -minor pathway via CYP450 to toxic metabolite then to non-toxic metabolite via glutathione

Question 35

What are the adverse effects of acetaminophen?

Answer 35

-few at normal doses*** -Stevens-Johnson syndrome -Toxic epidermal necrolysis -hepatotoxicity (OD or liver failure)

Question 36

What are the signs and symptoms of hepatic necrosis?

Answer 36

-N&V -diarrhea -sweating -abdominal pain

Question 37

What is the treatment for acetaminophen OD?

Answer 37

acetylcysteine via IV or oral - converts toxic metabolits to non-toxic form