How to prevent allopurinol hypersensitivity reactions?
Lisa K Stamp1,2, Murray L Barclay3
1Department of Medicine, University of Otago, Christchurch.
Rheumatology (Oxford, England)
|December 23, 2017
Summary
Allopurinol hypersensitivity syndrome (AHS) is a severe drug reaction. Preventive measures like HLA-B*5801 testing and patient education can reduce AHS risk, especially in gout patients.
Area of Science:
- Pharmacology
- Clinical Medicine
- Immunology
Background:
- Allopurinol hypersensitivity syndrome (AHS) is a severe, potentially fatal adverse drug reaction.
- Gout patients frequently require allopurinol, increasing the overall incidence of AHS.
- Early recognition and intervention are crucial for managing AHS.
Purpose of the Study:
- To review preventive strategies for allopurinol hypersensitivity syndrome (AHS).
- To evaluate the efficacy and cost-effectiveness of genetic screening and dose adjustments.
- To discuss risk factors and alternative treatments for AHS.
Main Methods:
- Literature review of AHS cases and preventive measures.
- Analysis of the role of HLA-B*5801 genetic testing.
- Evaluation of allopurinol dosing strategies and risk factors like chronic kidney disease.
Main Results:
- Most AHS cases occur within 8-9 weeks of allopurinol initiation.
- HLA-B*5801 testing and avoidance of allopurinol in positive individuals is effective and cost-effective in certain populations.
- Lower starting doses may reduce risk, while the maintenance dose-AHS relationship is debated.
- Chronic kidney disease increases AHS risk, but slow dose titration may be safe.
Conclusions:
- Patient education at allopurinol initiation can facilitate early symptom recognition and drug cessation.
- HLA-B*5801 screening is a valuable tool for preventing AHS in at-risk populations.
- Careful dose management and consideration of alternative therapies are important for patients susceptible to AHS.
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