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)