Aspirin and non-steroidal anti-inflammatory drugs (NSAIDS)

Question 1

Name the NSAID drugs and identify whether these are non-selective or selective inhibitors of COX

Answer 1

COX2 Selective inhibitor drugs: Celecoxib, parecoxib and meloxicam

Question 2

Describe the mechanism of action of and aspirin and of selective and non-selective COX1 and COX2 inhibitors

Answer 2

COX -> Converts arachidonic acid to prostaglandins

Isoforms of Cyclo-oxygenase (COX) - i.e. different versions of COX enzyme

1) COX1 -> Mediates physiological function of gastric mucosa, kidneys and intestines:
- Blocking COX1 leads to gastrointestinal toxicity
- COX1 is found in platelets

2) COX2 -> Mediates inflammation, pain and fever; mediates cardiovascular toxicities:
- Blocking COX2 leads to cardiovascular toxicity
- COX2 is only expressed in cells activated by pro-inflammatory cytokines

NSAIDS inhibit the activity of COX, especially COX-2 resulting in anti-inflammatory actions

Question 3

Describe the adverse effect profile that relates to this mechanism of action and describe how these adverse effects can be monitored or minimised

Answer 3

Adverse side effects:

• Osteoarthritis
• Potential toxicity (especially in elderly):
  1) Gastrointestinal toxicity (most common by far)
• Through COX-1 inhibition
• Ulcers and gastritis
  2) Risk factors:
• Age >65
• History of peptic ulcer disease or GI bleeding
• Use of anticoagulants
• Kidney toxicity (nephrotoxicity)
• Cardiovascular risk with selective COX-2 inhibitor NSAIDs

Question 4

Outline the issues associated with NSAID use and dentistry. When is caution required in the prescription of aspirin and the NSAIDs to dental patients?

Answer 4

• NSAID: group of analgesic and anti-inflammatory drugs

- First choice for pain and inflammation