Aspirin

Important adverse effects of aspirin

- GI upset - peptic ulceration - bronchospasm - regular high dose therapy can cause tinnitus

Symptoms of aspirin overdose

- early sign is ear rining - causes respiratory alkalosis first followed by metabolic acidosis

Mechanism of action of aspirin

irreversibly inhibits COX to reduce production of pro-aggregatory factor thromboxane this reduces platelet aggregation Effective at low doses and lasts for 7-10 days

Indications

1. treatment of ACS and ischaemic stroke 2. secondary prevention of major cardiovascular events 3. management of mild-moderate pain and fever

Important interactions with aspirin

Co-prescription with other anti-platelet drugs and anti-coagulants may increase risk with bleeding although co-prescription with ADP receptor antagonists is common

Warnings for aspirin use

X children under 16 (risk of Reye's syndrome) X aspirin hypersensitivity X third trimester of pregnancy Use with caution in - asthmatic patients - peptic ulcerations - gout (may trigger an attack)