Allergic reactions, drugs classification

Several workers have attempted to classify allergic drug reactions in terms of their underlying immunological mechanisms. Such a classification presupposes knowledge of their immunopathogenesis, and there are at present very few cutaneous drug reactions for which this is understood (Schulz 1972, 1974) ... 

Several types of adverse drug reactions do not easily fit into Cell and Coomb s classification scheme. These include most cutaneous hypersensitivity reactions (such as toxic epidermal necrolysis), immune-allergic hepatitis and hypersensitivity pneumonitis. Another difficulty is that allergic drug reactions can occur via more than one mechanism picryl chloride in mice induces both type 1 and type IV responses. Although other classification schemes have been proposed. Cell and Coomb s system remains the most widely utilized scheme [4-7]. 

Stevenson DD, Sanchez-Borges M, Szczeklik A. Classification of allergic and pseudoallergic reactions to drugs that inhibit cyclooxygenase enzymes. Ann Allergy Asthma Immunol 2001 87(3) 177-80. 

Table 2. Classification of allergic reactions to drugs according to the suspected immunologic mechanism...

The table established by Gell and Ccx)mbs is of importance when analyzing the type of immunologic reaction (Table 2). However, in this specific field of allergic reactions to drugs, there are several reactions which fail to enter into this practical but oversimplified classification. For instance ... 

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