NSAID's

Question 1

What does the term NSAIDS refer to?

Answer 1

Non-steroidal anti-inflammatory drugs. 
Used to:
1) Reduce pain.
2) Lower body temperature in a person with a fever.
3) Decrease inflammation

Question 2

What is the relationship between the enzymes ‘cyclo-oxygenase’ and ‘lipo-oxygenase’?

Answer 2

Cyclo-oxygenase facilitates the process by which arachidonic acid forms prostaglandins, prostacyclin and thromboxane A2.
Lipo-oxygenase facilitates the process by which arachidonic acid forms leukotrienes.

Question 3

Name the enzyme required to convert phospholipids to arachidonic acid.

Answer 3

Phospholipase A2

Question 4

Explain the function of the inflammatory process.

Answer 4

Inflammation is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molecular mediators. The function of inflammation is to eliminate the initial cause of cell injury, clear out necrotic cells and tissues damaged from the original insult and the inflammatory process, and initiate tissue repair.

Question 5

What is the role of prostaglandins in the inflammatory response?

Answer 5

PG increase vascular permeability, pain and fever. PG are powerful locally acting vasodilators and inhibit the aggregation of blood platelets and therefore blood clots.

Question 6

At what stage of the inflammatory process do NSAIDS exert their action?

Answer 6

NSAIDs block the COX enzymes and reduce production of prostaglandins. Therefore, inflammation, pain, and fever are reduced by all COX inhibitors.

Question 7

Why don’t NSAIDS completely eradicate the inflammatory process?

Answer 7

Other inflammatory mediators which are not related to cox are still present e.g. leukotrienes.

Question 8

If the inflammatory process is so beneficial for our survival, why do we even need anti- inflammatory drugs?

Answer 8

Associated swelling can be associated with morbidity and mortality

Question 9

Apart from NSAID’s, which is the other group of drugs frequently prescribed as anti- inflammatories?

Answer 9

Steroids.

Question 10

Name the 2 main sub-groups of NSAID’s. Describe in one sentence the fundamental difference between these 2 types, in terms of its mechanism of action.

Answer 10

1st generation and 2nd generation.

1st generation inhibits both cox 1 and cox 2. 2nd generation inhibits only cox 2.

Question 11

What does COX stand for? What are the differences between COX-1 and COX-2?

Answer 11

Cyclo-oxygenase
Cox 1 works on arachidonic acid that has been produced from a Physiological Stimulus,
Cox 2 works on arachidonic acid that has been produced from an Inflammatory Stimulus and has no affect on stomach and platelets (unlike cox1).

Question 12

Examples of 1st generation NSAID’s.

Answer 12

Paracetamol, Diclofenac, Indomethacin, Piroxicam, Mefanamic acid, Aspirin, Ibuprofen and Naproxen.

Question 13

Examples of 2nd generation NSAID’s.

Answer 13

Nimesulide, Rofecoxib, Celecoxib.

Question 14

Where are NSAIDS absorbed from when taken orally?

Answer 14

Small intestine.

Question 15

What other routes of administration are there?

Answer 15

Rectal and topical.

Question 16

Where are NSAID’s metabolised?

Answer 16

Liver.

Question 17

Where are they excreted from?

Answer 17

Kidney.

Question 18

Explain the mechanism by which NSAID’s exert their analgesic action?

Answer 18

1) Central analgesic effect in spinal cord.

2) Peripheral effect - desensitisation of afferent nerves (those nerves which carry information to the brain).

Question 19

Explain the mechanism by which NSAID’s exert their antipyretic action?

Answer 19

Inhibition of PG synthesis in the hypothalamus.

Question 20

Explain the mechanism by which NSAID’s exert their anti-inflammatory action?

Answer 20

Reduction of PG synthesis at site of

injury.

Question 21

Explain the mechanism by which NSAID’s can cause abnormal bleeding?

Answer 21

NSAIDs block the COX enzymes and reduce production of prostaglandins. Therefore, inflammation, pain, and fever are reduced by all COX inhibitors. Since the prostaglandins that protect the stomach and promote blood clotting also are reduced, NSAIDs can increase the risk of bleeding. So they inhibit platelet function.

Question 22

Explain the mechanism by which NSAID’s can cause gastrointestinal symptoms?

Answer 22

Inhibit the PG which normally protect

the gastric mucosa.

Question 23

Explain the mechanism by which NSAID’s cause problems in individuals with compromised cardiovascular function?

Answer 23

Increased risk of myocardial infarction with many (not asprin), probably due to effect on prostacyclin (prostacyclin is a vasodilator and inhibits platelet aggregation).

Question 24

Explain the mechanism by which NSAID’s damage the kidney?

Answer 24

Renal PG dilate afferent arterioles, thus maintain glomerular filtration. if these are inhibited, renal flow is affected.
Also, NSAID’s can cause two different forms of acute kidney injury. 1) Acute tubular necrosis. 2) Acute interstitial nephritis.

Question 25

What are the effects of NSAIDS in a pregnant woman?

Answer 25

NSAID’s may delay labour.

Question 26

What types of individuals need to take particular care when using NSAIDS?

Answer 26

Individuals with bleeding tendencies, gastric diseases (or history of), renal dysfunction, hypersensitvity reactions, elderly, CVS dysfunction.

Question 27

Match the generic drug name with the appropriate trade name.

Answer 27

GENERIC NAME / TRADE NAME
Paracetamol / Panadol, Panama.
Indomethacin / Indocin
Aspirin / Disprin, Cardiprin 
Naproxen / Naprosyn
Mefanamic acid / Ponstan
Ibuprofen / Nurofen, Brufen
Piroxicam / Feldene
Celecoxib / Celebrex
Diclofenac / Voltaren

Question 28

Why should children and adolescents with an ‘influenza-like’ illness NOT be given aspirin?

Answer 28

Reye syndrome.

Question 29

What would be the possible result of an individual overdosing on aspirin or paracetamol?

Answer 29

Asprin: fluid, electrolyte and acid-base imbalance (mixed respiratory alkalosis and a metabolic acidosis.) hepatic and nephrotoxicity.
Paracetamol: liver damage.