Pyrazolone hypersensitivity

Himly M, Jahn-Schmid B, Pittertschatscher K, Bohle B, Grubmayr K, Ferreira F, Ebner H, Ebner C IgE-mediated immediate-type hypersensitivity to the pyrazolone drug propyphenazone. J Allergy Chn Immunol 2003 111 882-888. 

Association of pyrazolone drug hypersensitivity with HLA-DQ and DR antigens. Clin Exp Allergy 1998 28 1153-1158. 

About 10% of asthmatics are hypersensitive to aspirin, and in some individuals life-threatening bronchoconstriction can occur. This is not a drug-drug interaction but an adverse response of asthmatic patients to aspirin, whether taking an anti-asthmatic drug or not. The reasons are not fully understood. Those known to be sensitive to aspirin may also possibly react to other NSAIDs, in particular the acetylated salicylates, the indole and indene acetic acids, and the propionic acid derivatives (see Table 6.1 , (p.l34)). The fenamates, oxicams, pyrazolones and pyrazolidinediones are better tolerated. The nonacetylated salicylates (sodium salicylate, salicylamide, choline magnesium trisalicylate) are normally well tolerated. Aspirin-sensitive individuals are also less likely to react to nimesulide. ... 

There is a group of patients who are hypersensitive to pyrazolone analgesics, but not to the aspirin-like drugs (Szczeklik et al. 1977 a). These patients, more often... 

As anti-inflammatory drugs, pyrazolone preparations have been used topically for superficial phlebitis and similar inflammatory conditions. Krook (1975) described three cases of contact allergy, one sensitive to oxyphenbutazone, the two others sensitive to phenylbutazone. Phenylbutazone did not cause cross-sensitivity to oxyphenbutazone, while cross-sensitivity the opposite way was found. Vooys and Van Ketel (1977) added one more case of phenylbutazone allergy, and Thormann and Kaaber (1978) recorded four, emphasizing the increased risk of developing hypersensitivity in patients with preexisting skin disorders. 

Maculopapular eruptions Ibuprofen, flurbiprofen, diclofenac, pyrazolones, celecoxib Probably specific T cell hypersensitivities... 

Reactions to pyrazolone drugs can resemble AIA or be type I IgE-mediated hypersensitivity. 

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