What is the risk of using Acetylsalicylic Acid (ASA) in patients with asthma?

Risk of Acetylsalicylic Acid (ASA) in Patients with Asthma

Acetylsalicylic acid (ASA) is contraindicated in patients with asthma who have a history of ASA sensitivity due to the risk of potentially life-threatening bronchospasm. 1, 2

Prevalence and Mechanism

• Approximately 10% of adults with asthma and a smaller proportion of children experience respiratory deterioration when taking ASA or other NSAIDs 3
• The prevalence of aspirin hypersensitivity ranges from 0.6% to 2.5% in the general population and from 4.3% to 11% in adult asthmatics 4
• ASA-induced asthma is characterized by overproduction of cysteinyl-leukotrienes (Cys-LTs) and intense eosinophilic inflammation of nasal and bronchial tissues 5
• The mechanism involves inhibition of cyclooxygenase enzymes, leading to overproduction of leukotrienes and removal of the bronchodilator effect of prostaglandin E2 6

High-Risk Patients

• Patients with the following features are at highest risk for ASA-induced bronchospasm:
  • Severe asthma 3
  • Nasal polyps 3, 4
  • Chronic rhinosinusitis 3, 4
• The classic presentation (Samter's Triad) includes: aspirin-induced bronchial asthma, aspirin sensitivity, and chronic rhinosinusitis with nasal polyps 4

Clinical Presentation

• Within 3 hours of ASA ingestion, sensitive individuals may develop:
  • Bronchoconstriction 6
  • Rhinorrhea 6
  • Conjunctival irritation 6
  • Scarlet flush 6
• In severe cases, a single therapeutic dose can provoke:
  • Violent bronchospasm 6
  • Loss of consciousness 6
  • Respiratory arrest 6

Recommendations for ASA Use in Asthma

• ASA and other NSAIDs are absolutely contraindicated in patients with known ASA intolerance 1, 2
• The FDA drug label specifically warns that ASA may cause asthma (wheezing) and should not be used by patients with asthma without consulting a doctor 2
• Patients with uncontrolled or severe asthma should avoid ASA due to increased risk of severe exacerbations 1
• For patients with asthma who have never used NSAIDs before, medical supervision is recommended for first-time use 3

Alternative Approaches

• Acetaminophen (paracetamol) is generally considered safer for patients with ASA-sensitive asthma, though a small proportion may still experience respiratory deterioration with high doses 3
• For patients who absolutely require ASA therapy (e.g., for cardiovascular disease), options include:
  • ASA desensitization therapy under medical supervision 6, 4
  • Selective COX-2 inhibitors may be considered as alternatives in some cases 6

Special Considerations

• ASA desensitization can be successful initially but sensitivity may recur despite continuous therapy 7
• Patients with both cardiovascular disease and asthma require careful risk-benefit assessment when considering ASA therapy 1
• Patients with asthma who regularly use NSAIDs without problems can continue but should be warned that intolerance can develop later in life 3

Diagnostic Approach

• For patients with suspected ASA sensitivity, oral, inhaled, nasal, or intravenous aspirin challenge tests can be performed 6
• These tests should only be conducted in facilities with experienced physicians and emergency treatment available 6

ASA-induced asthma represents a significant risk for certain asthmatic patients. Healthcare providers should carefully assess the risk-benefit ratio before prescribing ASA to patients with asthma, particularly those with high-risk features such as nasal polyps or severe asthma.