Non-opioid analgesics

Question 1

NSAIDs are inhibitors of what?

Answer 1

Cyclooxygenase (COX) which catalyzes first step in synthesis of prostaglandins from arachidonic acid and other precursor fatty acids.

Question 2

Net effect of NSAIDs on prostaglandins?

Answer 2

Decrease in production of prostaglandins and other autacoids.

Question 3

Indications for NSAIDs?

Answer 3

Antipyretic, analgesic, and anti-inflammatory (except acetaminophen which is not anti-inflammatory)

Question 4

Side effects of NSAIDs?

Answer 4

GI irritation, peptic ulcers (less with celcoxib)
Increased bleeding/bruising
Hepatic toxicity (esp with acetaminophen)
Renal toxicity (except with acetaminophen)

Question 5

NSAIDs during preganancy?

Answer 5

Teratogenicity: Use of NSAIDs during second half of pregnancy is not recommended because of potential adverse effects on fetus from prostaglandin inhibition. Can lead to Gi bleeding, platelet dysfunction, renal dysfunction, premature closure of ducutus arteriosus (exception is acetaminophen which can be used for analgesia and antipyresis during pregnancy).

Question 6

Aspirin: MOA

Answer 6

Low doses have antiplatelet effects because they acetylate and irreversibly inhibit platelet COX.

Low doses also have analgesic and antipyretic effects. Higher doses are needed to counteract inflammation.

Question 7

Aspirin: Indications

Aspirin is used as prophylactic drug for which conditions?

Answer 7

Management of pain, fever, inflammation, prophylaxis of MI, stroke, and other thromboembolic disorders.

Question 8

Aspirin: Side effects

Answer 8

High doses of aspirin can cause tinnitus. Toxic doses cause hyperventilation, respiratory alkalosis, followed by metabolic acidosis.

In kids, salicylates should be avoided because of risk of Reye syndrome (happens in virus-infected kids who are treated with these drugs).

Question 9

Aspirin: Metabolism/Procedure for Overdose

Answer 9

Aspirin toxicity: Induce vomiting and give sodium bicarbonate to counteract metabolic acidosis and increase urinary excretion of salicyclic acid.

Question 10

Indomethacin: Indication

Answer 10

Treat patent ductus arteriosus

Question 11

Nonselective cyclooxygenase inhibitors?

Answer 11

Aspirin, ibuprofen, indomethacin, naproxen, ketorolac, diclofenac

Question 12

Ketorolac: Indication

Answer 12

Short-term management of moderate pain, such as postoperative pain associated with dental surgery. Can be given orally or parenterally.

Question 13

Ketorolac: Side effects

Answer 13

Hematologic toxicity is possible. Ketorolac should only be used for a few days to avoid this.

Question 14

Diclofenac: How is it given to patients?

Answer 14

Can be given via transdermal patch or a topical formulation.

Question 15

Selective COX-2 inhibitors?

Answer 15

Celecoxib

Question 16

Selective COX-3 inhibitors?

Answer 16

Acetaminophen

Question 17

Celecoxib: MOA

Answer 17

Provides potent anti-inflammatory activity without causing significant GI toxicity.

Question 18

Celecoxib: Side effects

Answer 18

Increased risk of cardiovascular events. Cardiotoxicity is especially a concern with selective COX-2 inhibitors.

Question 19

Acetaminophen: Indications?

Answer 19

Treatment of mild pain and fever. Exerts analgesic and antipyretic effects during ST administration. Unlike aspirin, acetaminophen is NOT associated with Reye syndrome so it can be given to kids.
Acetaminophen has WEAK anti-inflammatory activity.

Question 20

Acetaminophen: Side effects

Answer 20

Metabolite of acetaminophen is a hepatotoxic quinone intermediate. The metabolite is inactivated by conjugation with glutathione, but toxic doses of acetaminophen can deplete glutathione and cause fatal liver failure.

Question 21

What is antidote for acetaminophen toxicity?

Answer 21

Acetylcysteine