Polyethylene glycols are used as solvent and excipient in topical or systemic drugs, as active principle of drugs, in electrodes gels, insect repulsives, cosmetic and hy- giene products, cutting fluids, glue and epoxy hardeners (plasticizers; 1). There are many PEGs derivatives, such as ceto- macrogol, lauromacrogol, nonoxynol. One case of anaphylaxis to macrogol after an intra-articular injection of cor- ticoid has been reported (2). We found rare reports of bronchospasm, anaphy- laxis, urticaria or angioedema after ingestion of PEGs solutions for prepar- ation before coloscopy but no allergo- logical exploration was made (3). This observation underlined that al- lergy to excipients even if it is a rare event should be considered, a fortiori if there are multiple allergic reactions. To our knowledge, it is the first case of anaphy- lactic shock to macrogol after oral intake and contact urticaria to topical drugs containing macrogols in the same patient. *Dermatology Unit St-Eloi Hospital 80 avenue Augustin Fliche 34295 Montpellier cedex 5 France Tel: +33 467 336956 Fax: +33 467 336958 E-mail: hcominh@yahoo.fr Accepted for publication 1 October 2006 Allergy 2007: 62:92–93 Ó 2007 The Authors Journal compilation Ó 2007 Blackwell Munksgaard DOI: 10.1111/j.1398-9995.2006.01265.x References 1. Rietschel RL, Fowler JF Jr. Fisher’s contact dermatitis. Philadelphia: Lippincott Williams and Wilkins, 2001:235. 2. Dewachter P, Mouton-Faivre C. Anaphylaxis to macrogol 4000 after a parenteral corticoid injection. Allergy 2005;60:705–706. 3. Stollman N, Manten HD. Angioedema from oral polyethylene glycol electrolyte lavage solution. Gastrointest Endosc 1996;44:209–210. Sulfonamide allergy without cross-reactivity to celecoxib J. Figueroa*, N. Ortega, L. Almeida, C. Blanco, R. Castillo Key words: celecoxib; cross-reaction; cross- sensitization; drug allergy; sulfonamides. Cross-sensitization between sulfonamides and celecoxib has been discussed in the last years (1–4), although a real cross- reactivity between them has not been demonstrated. We report here five patients with sul- famethoxazole allergy confirmed by sin- gle-blind placebo-controlled oral challenge (SBPCOC) who tolerated oral challenge tests with celecoxib. We recruited patients that had been diag- nosed of sulfonamide allergy confirmed by a positive oral provocation test in the last 4 years. Five patients were included in the study after obtaining written informed consent. The mean age of the sulfonamide allergy group of patients was 32 ± 12.21 years (mean ± SD), with a predominance of females (4 : 1), and all of them had a history of sulfomethoxaz- ole allergy confirmed by SBPCOC as shown in Table 1. We performed SBP- COC with celecoxib reaching a cumula- tive dose of 200 mg obtaining a negative result in all patients. Celecoxib is usually avoided in patients who have demonstrated allergic reactions to sulfonamides although there is a con- troversy about possible cross-reactions between sulfonamides and celecoxib. In fact few cases of clinically relevant possible cross-sensitization between these two drugs have been reported in litera- ture. Celecoxib is a sulfonamide-containing drug without an aromatic amine and without a substituted ring at the N1- position, so it is chemically distinct from the arylamine sulfonamide antimicrobi- als, and these differences are responsible of the lower potential for causing hyper- sensitivity reactions of celecoxib (2, 3). A meta-analysis of 14 double-blind stud- ies showed that celecoxib, nonsulfona- mide-containing nonsteroidal anti- inflammatory drugs and placebo have comparable potentials for cross-reactivity with sulfonamide-containing drugs (4). In this study, no cross-sensitization between celecoxib and sulfomethoxazole was found. Although further investiga- tions are necessary, scientific data at the moment show no evidence to avoid using celecoxib in patients with a known sul- fonamide allergy, at least until possible cross-reaction could be confirmed by an oral challenge with the cyclo-oxygenase-2 inhibitor agent. *Hospital Universitario Insular de Gran Canaria Allergy Section Avda Marı´tima del Sur s/n none Las Palmas de Gran Canaria 35016 Tel: +34 928 441416 Fax: +34 928 441869 E-mail: jafiri@hotmail.com Accepted for publication 10 October 2006 Allergy 2007: 62:93 Ó 2007 The Authors Journal compilation Ó 2007 Blackwell Munksgaard DOI: 10.1111/j.1398-9995.2006.01270.x References 1. Schuster C, Wu¨ thrich B. Anaphylactic drug reaction to celecoxib and sulfamethoxazole: cross reactivity or coincidence? Allergy 2003;58:1072. 2. Knowels S, Sahapiro L, Shear NH. Should celecoxib be contraindicated in patients who are allergic to sulfonamides? Drug Saf 2001;24:239–247. 3. Clemett D, Goa KL. Celecoxib: a review of its use in osteoarthritis, rheumatoid arthritis an acute pain. Drugs 2000;59:957–980. 4. Patterson R, Bello AE, Lefkowith J. Immunologic tolerability profile of celecoxib. Clin Ther 1999;21:2065–2079. Table 1. Clinical characteristics of sulfonamide allergy patients Patient number Age (years) Sex Clinical symptoms in sulfamethoxazole oral challenge 1 17 Female Urticaria 2 45 Female Urticaria 3 25 Male Anaphylaxis 4 44 Female Urticaria 5 29 Female Angioedema ALLERGY Net 93