Aspirin

What is aspirin?

NSAID

What are the indications of aspirin?

- Adults with clinical or ECG evidence suggestive of a myocardial infarction or ischemia
- Suspected TIA, but only when symptoms have completely resolved, and the patient is not being taken to hospital but is being referred to a local TIA pathway

What are the contraindications of aspirin?

- Known aspirin allergy/ sensitivity
- Children under 16 as this may cause Reye’s Syndrome, which can -damage young children’s liver and brain
- Active gastrointestinal bleeding
- Severe hepatic failure with jaundice
- Haemophilia or other known clotting disorders
- Breast feeding – avoid due to risk of Reye's syndrome

What are the effects of aspirin?

- Antipyretic
- Anti-inflammatory 
- Analgesic
- Anti-platelet

What are the side effects of aspirin?

- Increased risk of gastric bleeding
- Wheezing (bronchospasm) in some asthmatics or exacerbation of asthma

What are the cautions of aspirin?

As the benefits outweigh the potential risks (with a single 300 milligram dose), aspirin can be administered to patients with: 
- Asthma
- Pregnancy- used with caution in third trimester as can lead to delayed onset and increased duration of labour with increased blood loss. High doses may lead to persistent pulmonary HPT in newborn
- Renal failure - be cautious of fluid retention and further renal impairment
- Moderate hepatic disease without jaundice- avoid in sever impairment
- Gastric or duodenal ulcer
- Current  anticoagulant treatment

How does aspirin affect pain, inflammation, fever and swelling?

Aspirin inhibits the activity of enzyme Cyclooxygenase (COX-1). This enzyme leads to the formation of prostaglandins that cause inflammation, pain, fever and swelling. Prostaglandins are potent, irritating substances that cause headaches and pain. They increase sensitivity of pain receptors and substances such as histamine

Why is aspirin an antipyretic agent?

Due to its ability to interfere with production of the brain prostaglandin E1- a powerful fever-inducing agent

How does aspirin affect platelet aggregation?

- Thromboxane B2 (TxB2) is an important lipid responsible for platelet aggregation, which can lead to clot formation and future risks of strokes and MI's
- Inhibition of platelet aggregation by aspirin occurs due to its interference with TxB2, caused by COX-1 inhibition

How is aspirin administered?

Enteral- Chewed or dissolved tablets in water, max dose of 300mg  tablet max dose