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Anticonvulsant hypersensitivity syndrome: implications for pharmaceutical care
KarenBeth H Bohan1, Tarannum F Mansuri, Natalie M Wilson
1Department of Pharmacy Practice, Nesbitt College of Pharmacy and Nursing, Wilkes University, Wilkes-Barre, Pennsylvania 18766, USA.
Pharmacotherapy
|September 28, 2007
Summary
Anticonvulsant hypersensitivity syndrome (AHS) is a rare but severe drug reaction to aromatic anticonvulsants. Early recognition of rash, fever, and organ involvement is key for management, often involving drug withdrawal and corticosteroids.
Area of Science:
- Pharmacology
- Immunology
- Toxicology
Background:
- Anticonvulsant hypersensitivity syndrome (AHS) is a severe, delayed adverse drug reaction.
- It is primarily linked to aromatic anticonvulsant drugs like phenytoin, carbamazepine, and phenobarbital.
- AHS occurs rarely, affecting 1 in 1000-10,000 exposures, but can lead to hospitalization and death.
Purpose of the Study:
- To provide a comprehensive overview of Anticonvulsant hypersensitivity syndrome (AHS).
- To discuss the clinical manifestations, diagnostic criteria, and proposed mechanisms of AHS.
- To outline current management strategies and emphasize prevention through patient and family education.
Main Methods:
- Review of clinical manifestations including dermatologic rashes, fever, and systemic organ involvement.
- Discussion of diagnostic approaches based on symptom triad and clinical judgment.
- Exploration of proposed pathophysiological mechanisms involving epoxide hydroxylase, viral reactivation, and genetic factors.
Main Results:
- AHS presents with a characteristic triad of rash, fever, and organ involvement.
- Potential mechanisms include impaired drug metabolism, viral reactivation, and genetic predisposition (HLA subtypes).
- Cross-sensitivity among aromatic anticonvulsants ranges from 40-80%, necessitating avoidance of these drugs in affected patients.
Conclusions:
- AHS management requires prompt discontinuation of the offending aromatic anticonvulsant drug.
- Systemic corticosteroids are typically needed for recovery.
- Valproic acid and benzodiazepines are considered safer alternatives; pharmacists play a crucial role in AHS prevention and management.
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