title: Safety of celecoxib in individuals allergic to sulfonamide: a pilot study.
abstract: OBJECTIVE
  To evaluate cross reactivity between sulfonamide antimicrobials and celecoxib in patients with histories of allergies to sulfonamide antimicrobials.
  
  
  METHODS
  Immunocompetent patients with a history of sulfonamide antimicrobial allergy who were being considered for therapy with celecoxib were prospectively enrolled. Sulfamethoxazole and trimethoprim skin prick and intradermal testing and/or an in vitro lymphocyte toxicity assay were performed. If skin testing was negative, an oral challenge with sulfamethoxazole and trimethoprim was performed. Oral challenges with celecoxib were administered to all patients.
  
  
  RESULTS
  Twenty-eight immunocompetent patients (26 female; mean age 60 years) were evaluated. History of sulfonamide antimicrobial allergy included urticaria (n = 7), cutaneous eruptions (n = 9), and other (n = 12). Four of the 28 patients who were skin prick tested were positive to sulfamethoxazole and two of the ten patients who underwent in vitro testing were positive to sulfamethoxazole. All 28 patients were administered celecoxib and tolerated the medication. Phone call follow up in 25 patients disclosed that 15 patients continued to take celecoxib, while five patients did not take celecoxib following the oral challenge, and five discontinued celecoxib due to adverse effects, lack of drug efficacy or physician preference.
  
  
  CONCLUSIONS
  Confusion exists regarding the potential for cross reactivity between sulfonamide antimicrobials and other sulfonamide-containing compounds. The six sulfonamide-allergic patients tolerated celecoxib uneventfully. This pilot study supports the hypothesis that the potential for cross-reactivity between celecoxib and sulfonamide antimicrobials appears to be low. However, further investigations are required to confirm this.
authors.affiliation: Division of Clinical Pharmacology, Drug Safety Research Group, University of Toronto, Toronto, Ontario, Canada. lori@mindcharger.com
authors.forename: Lori E
authors.initials: LE
authors.lastname: Shapiro
authors.forename: Sandra R
authors.initials: SR
authors.lastname: Knowles
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Weber
authors.forename: Manuela G
authors.initials: MG
authors.lastname: Neuman
authors.forename: Neil H
authors.initials: NH
authors.lastname: Shear
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000368:Aged; D000890:Anti-Infective Agents / Q000009:adverse effects*; D000068579:Celecoxib; D003429:Cross Reactions; D016861:Cyclooxygenase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects* / Q000737:chemistry; D003875:Drug Eruptions / Q000209:etiology; D004342:Drug Hypersensitivity / Q000209:etiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010865:Pilot Projects; D011720:Pyrazoles; D012882:Skin Tests; D013449:Sulfonamides / Q000008:administration & dosage / Q000009:adverse effects* / Q000737:chemistry; D015662:Trimethoprim, Sulfamethoxazole Drug Combination
chemical_list: D000890:Anti-Infective Agents; D016861:Cyclooxygenase Inhibitors; D011720:Pyrazoles; D013449:Sulfonamides; D015662:Trimethoprim, Sulfamethoxazole Drug Combination; D000068579:Celecoxib