Irreversible COX Inhibitors Flashcards Preview

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Flashcards in Irreversible COX Inhibitors Deck (20)
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1
Q

Give an example of an irreversible COX inhibitor

A

Aspirin

2
Q

What is the mechanism of action of aspirin?

A
  • Irreversibly inhibits COX

- Irreversibly inhibits thromboxane A2

3
Q

What is COX involved in?

A

Prostaglandin release

4
Q

What is thromboxane A2 needed for?

A

Platelet aggregation

5
Q

What is the result of the inhibition of thromboxane A2?

A

Prevents blood from clotting and forming thrombus

6
Q

What is the route of delivery of aspirin?

A

PO

7
Q

What are the indications for aspirin?

A
  • Treatment of MI
  • Prophylaxis of MI
  • Pregnant women at high risk of pre-eclampsia
8
Q

How is aspirin given in the treatment of MI?

A

Usually as 300mg stat dose

9
Q

How is aspirin given in the prophylaxis of MI?

A

Usually 75mg OD

10
Q

When is aspirin used in pregnant women at high risk of pre-eclampsia?

A

Can be taken from week 12 to delivery

11
Q

What are the contraindications to aspirin?

A
  • Patients on anti-platelet drugs, e.g. clopidogrel
  • Patients at high risk of bleeding, e.g. haemophiliacs
  • Peptic ulceration
  • Known hypersensitivity to aspirin or NSAIDs
  • Children under 16
12
Q

Who should aspirin be used with caution in?

A
  • Asthma
  • Anaemia
  • Elderly
  • During 3rd trimester of pregnancy
13
Q

What might aspirin interact with?

A
  • NSAIDs
  • Anticoagulants
  • SSRIs
14
Q

What are the side effects of aspirin?

A
  • May induce bronchospasm in asthmatics
  • Peptic ulceration
  • GI bleeding
  • Tinnitus
  • Nasal polyps
15
Q

What can be done to prevent peptic ulceration with aspirin?

A

PPI may be co-prescribed

16
Q

When might the side effects of tinnitus and nasal polyps occur with aspirin?

A

At analgesic doses, which may be higher than dose used for secondary prevention of cardiac events

17
Q

What counselling is required with aspirin?

A
  • How to take aspirin
  • Prolonged bleeding
  • Not for children
18
Q

How should aspirin be taken?

A

Non-dispersible aspirin should not be chewed. Should be swallowed whole with food, and indigestion remedies should be avoided at the time of aspirin consumption

19
Q

What should the patient be told regarding prolonged bleeding?

A

Aspirin may cause a patient to bleed more or to bleed longer if they sustain an injury. Such symptoms should be reported to the patient’s GP

20
Q

Why should aspirin not be given to children under 16?

A

Due to risk of causing Reye’s syndrome