💊370: Analgesics + Antipyretics

Question 1

What is the mechanism of action of COX inhibitors?

Answer 1

Shift Arachidonic Acid to be turned into more leukotrienes

🚨ASTHMA pts- May have bad rxns

Question 2

What is the impact of COX-1 on the body?

Answer 2

1. Stomach: promotes PGE2+PGI2 = Gastroprotective = ⬇️ gastric acid secretion, ⬆️ bicarb+mucus secretion, maintains submucosal blood flow
2. Platelets: prompts TXA2 ➡️ stimulates platelet aggregation
3. Kidneys: promotes PGE2+PGI2 ➡️ stimulates renal vasodilation and blood flow (protective)

Question 3

What are the effects of COX2 on the body?

Answer 3

1. Tissue injury: promotes PGE2 ➡️ contributes to pain + inflammation
2. Brain: promotes prostaglandins ➡️ mediates fever + pain perception
3. Bronchial smooth muscle: relaxed by PGE1+PGE2+ PGI1
4. Colon: promotes prostaglandins ➡️ promotes colorectal cancer***
5. Uterus: PGE1+PGE2+PGEF2a promotes contractions at term

Question 4

What is the distinction between COX1 and COX2?

Answer 4

COX1 = GOOD, found in tissues constitutive

COX2 = BAD, inducible at sites of injury BUT good for kidneys

Question 5

What are the 1st Generation NSAIDs?

Answer 5

1. Aspirin (ASA)
2. Ibuprofen
3. Naproxen (Aleve)
4. Ketorolac (Toradol)

Question 6

Can aspirin be used for children 18years and under?

Answer 6

NO!! Risk of REYE’s SYNDROME

= encephalopathy, fatty liver, high risk postviral illness

Question 7

What are symptoms of salicylism?

Answer 7

1. Tinnitus
2. Sweating
3. Headache
4. Dizziness

= Hugh doses of ASA (uncommon)

Question 8

What is a prototype of a 2nd generation NSAID?

Answer 8

Celecoxib (Celebrex)

“-coxib”

Question 9

What is the mechanism of action for coxibs?

Answer 9

Selectively inhibit COX2 over COX1

Used to suppress pain and inflammation

Question 10

What has the highest risk of CV events out of all NSAIDs?

Answer 10

2nd Gen = coxibs

Question 11

What are prototypes of Topical NSAIDS?

Answer 11

1. Voltearen Emulgel (OTC)

2. Pennsiad (Rx)

Question 12

What is the mechanism of action for Acetaminohen?

Answer 12

Inhibition of COX in CNS, NOT peripheral

**no anti-inflammatory activity

Question 13

What are side effects of Acetaminophen?

Answer 13

1. Acute liver failure (MAX 4g/day, 3G/day for chronic use, 2.0-2.6 for chronic alcohol use/liver dmg)

Question 14

What is the antidote to acetaminophen?

Answer 14

Acetylcysteine (IV/PO)

= Repletes Glutathione stores

Question 15

Uremia

Answer 15

1. Renal function declines to 10%
2. Uremic toxins accumulate
3. Sudden (trauma, shock, toxins) OR chronic (HTN, diabetes)
4. Reversible or irreversible

Treatment: drug or dialysis

Question 16

What is Glomerular Filtration Rate (GFR)?

Answer 16

Flow rate of filtered fluid through the kidney

Difficult to measure precisely

Question 17

What is Creatinine Clearance (CrCl)?

Answer 17

Volume of blood cleared of creatinine per unit time

Approximates GFR