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Published on: December 15, 2011
Hypersensitivity reaction to desipramine.
The Journal of Allergy and Clinical Immunology
|July 1, 1987
Summary
Tricyclic antidepressants like desipramine can cause eosinophilia and elevated IgE. Desipramine directly triggers mast cell degranulation, explaining these adverse drug reactions.
Area of Science:
- Pharmacology
- Immunology
- Pulmonology
Background:
- Tricyclic antidepressants (TCAs) imipramine and desipramine are associated with adverse reactions.
- These reactions include eosinophilia, pulmonary infiltrates, and elevated serum IgE.
- The underlying immunologic mechanism remains unclear.
Observation:
- A patient presented with bronchospasm, marked eosinophilia, and high serum IgE levels.
- These symptoms occurred after initiating desipramine therapy.
- Symptoms resolved quickly upon discontinuing desipramine.
Findings:
- Immunologic tests did not reveal specific IgE against desipramine-protein conjugates.
- Direct intradermal skin challenges showed desipramine induces mast cell degranulation.
- This suggests a direct mast cell activation pathway.
Implications:
- Desipramine-induced mast cell degranulation may explain associated eosinophilia and IgE elevation.
- This finding offers insight into the immunologic basis of TCA adverse reactions.
- Understanding this mechanism could inform safer prescribing practices for TCAs.
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