Short communication Etoricoxib: a safe alternative for NSAID intolerance in Asian patients Genevieve V. Llanora,1 Evelyn Xiu Ling Loo,2 Irvin Francis A. Gerez,1 Yew Kuang Cheng 3,4 and Lynette P. Shek 1,2 Summary the patients had multiple symptoms on presentation, the most common of which were Background: NSAID intolerance is not uncommon. periorbital and facial edema (90%), breathing Etoricoxib, a cox-2 inhibitor NSAID, has been difficulties (26%) and urticaria (25%), with the shown to be a safe alternative in these patients. onset of reaction occurring mostly within 30 This study aims to determine the rate of NSAID minutes to 1 hour. Etoricoxib was tolerated in intolerant patients who are able to tolerate 95% of the patients. Subjects who reacted to the etoricoxib without adverse reactions. challenge all had mild reactions which resolved Methods: This study analyzed charts and with antihistamines. electronic databases of all patients referred to the Conclusions: Etoricoxib is a safe alternative in allergy clinics of the National University Hospital NSAID intolerant patients. Nevertheless, it is and Gleneagles Hospital in Singapore from 2006- advised that patients should undergo provocation 2011 for oral provocation tests to etoricoxib tests to confirm tolerance. (Asian Pac J Allergy (cumulative dose of 120mg), on the background Immunol 2013;31:330-3) of NSAID intolerance. Demographics, atopic comorbidities, history of chronic urticaria, Key words: Non-steroidal anti-inflammatory drug, inciting NSAID, onset and type of reaction, and drug reaction, oral provocation test provocation test outcomes were obtained. Introduction Results: A total of 74 patients (mean age 37; Non-steroidal anti-inflammatory drugs (NSAIDs) range: 16-72 years) underwent provocation tests are medications commonly used to alleviate pain to etoricoxib. Of these, 59% were female. and inflammation. It is estimated that over 30 Majority were Chinese (69%), followed by Malay million people worldwide consume it, with the trend (12%), Caucasian (8%), Indian (5%) and various increasing in the past 20 years. 1,2 The prevalence of other races (6%). Forty-six percent of the study NSAID intolerance ranges from 0.6-2.5% in the population had atopic comorbidities, and 4% had general population, to as high as 30% in patients concomitant chronic urticaria. Eighty percent of with asthma, nasal polyposis, and chronic idiopathic patients had a history of intolerance to 1 NSAID, urticaria. 2,3 In different populations, it currently while the rest (20%) had intolerance to multiple ranks second or third to the beta-lactam antibiotics NSAIDS. Forty-one percent of patients had in producing “allergic-type” drug reactions. concomitant acetaminophen intolerance. Some of NSAID-induced reactions can be classified as immunologic and non-immunologic. Immunologic From 1. University Children’s Medical Institute, National reactions can be in the form of an immediate University Hospital, Singapore hypersensitivity reaction (IgE mediated), or a type 2. Department of Paediatrics, Yong Loo Lin School of IV allergic reaction through drug-specific cytotoxic 2 Medicine, National University of Singapore T cells. For NSAIDS, the most well described 3. Department of Medicine, Yong Loo Lin School of reaction is non-immunologic and involves inhibition Medicine, National University of Singapore of the 2 isoforms of the cyclooxygenase enzyme 4. Gleneagles Medical Centre, Singapore (cox-1 and cox-2), thereby decreasing the production of Corresponding author: Genevieve V. Llanora potent inflammatory mediators, namely prostaglandin 2,4 E-mail: [email protected] and thromboxane. Inhibition of prostaglandin Submitted date: 22/8/2012 induces mast cell degranulation. With the inhibition Accepted date: 6/11/2012 of the cyclooxygenase pathway, the lipooxygenase pathway is favored, producing leukotriene, which 330 Etoricoxib is safe for NSAID intolerant patients promotes bronchoconstriction. 5 These mechanisms patients had multiple symptoms upon ingestion of are responsible for the signs and symptoms the inciting NSAID. The most common symptoms exhibited by NSAID intolerant patients. on presentation were periorbital and facial edema The therapeutic effects are primarily related to (90%), breathing difficulties (26%) and urticaria their ability to inhibit the cox-2 pathway, and the (25%), with the onset of reaction occurring mostly most frequent adverse effects are caused by cox-1 within 30 minutes to 1 hour. As some patients with inhibition. 4 It has been thought that specific cox-2 NSAID intolerance have concomitant acetaminophen inhibitor NSAIDs such as etoricoxib can be a intolerance, the history of concurrent acetaminophen potential safe alternative for patients with adverse intolerance was also determined. However, the reactions to NSAIDs. Indeed, this has been shown in definite dose that triggered the reaction was not 2 previous studies where most of the NSAID stated, as these were only obtained from medical intolerant patients who underwent provocation tests records, and not proven by provocation tests. It were able to tolerate etoricoxib. 6,7 showed an incidence rate of 41%, comparable to the In Asia, the exact prevalence of NSAID study done by Borges and Hulett, where 32% of intolerance is unknown. Furthermore, there are no patients with NSAID intolerance reacted to studies or reports on the tolerability to etoricoxib acetaminophen during provocation testing. 8 Table 1 among these patients. Thus, this is the first study in describes the general characteristics if the study Asia that aims to determine the safety of using population. etoricoxib in NSAID-intolerant patients. Table 1. General characteristics of the study population Methods Concomitant etoricoxib This study reviewed charts and electronic intolerance databases of all patients referred for NSAID YES NO P- intolerance to two allergy units in Singapore, one at 4/74 70/74 value the National University Hospital (NUH) and the (5%) (95%) other at Gleneagles Medical Centre (GMC), from Atopic comorbidities 2006-2011. These patients underwent oral Positive* 34/74 3/4 31/70 0.328 provocation tests to a cumulative dose of 120 mg of (46%) (75%) (44%) etoricoxib. In NUH, etoricoxib was given in 3 -Asthma 3/4 11/70 0.515 divided doses, 30 minutes apart(1 st dose: 30mg, 2 nd (25%) (16%) dose: 30mg, 3 rd dose: 60mg) whereas in GMC, it -Allergic rhinitis 3/4 21/70 0.097 was given in 4 divided doses (1 st dose: 15mg, 2 nd (75%) (30%) dose: 15mg, 3 rd dose: 30mg, 4th dose: 60mg). -Atopic dermatitis 1/4 4/70 (6%) 0.249 Information such as demographic data, atopic (25%) comorbidities, history of chronic urticaria, inciting Negative 40/74 1/4 39/70 0.328 (54%) (25%) (56%) NSAID, onset and type of reaction, presence or Chronic 3/74 1/4 2/70 (3%) 0.156 absence of concomitant acetaminophen intolerance, urticaria (4%) (25%) and provocation test outcomes were obtained. This Reaction study was approved by the Institutional Review To single NSAID 59/74 2/4 57/70 0.181 Board (NHG Domain Specific Review Board; (80%) (50%) (81%) Reference number 2011/01851). To multiple 15/74 2/4 13/70 0.181 NSAIDs (20%) (50%) (19%) Results Type of reactions to NSAIDS+ A total of 74 patients (mean age 37; range: 16-72 Cutaneous signs years) underwent provocation tests to etoricoxib. Of and symptoms these, 59% were female. Majority were Chinese Periorbital and 66/74 3/4 63/70 0.374 (69%), followed by Malay (12%), Caucasian (8%), facial edema (90%) (75%) (90%) Indian (5%) and various other races (6%). Forty-six Urticaria 18/74 1/4 17/70 1.000 (25%) (25%) (24%) percent of the study population had atopic Breathing 19/74 0 19/70 0.567 comorbidities, and 4% had concomitant chronic difficulties (26%) (27%) urticaria. Eighty percent of patients had a history of *Some patients have multiple comorbidities intolerance to 1 NSAID, while the rest (20%) had +Some patients presented with multiple signs and symptoms intolerance to multiple NSAIDS. Some of the 331 Asian Pac J Allergy Immunol 2013;31:330-3 DOI10.12932/AP0290.31.4.2013 Table 2. Clinical characteristics of eto ricoxib intolerant patients Cumulative History Patient Drug Concomitant OPT with dose of Atopic of Inciting Clinical number/ pattern acetaminophen etoricoxi etoricoxib Treatment Disease chronic NSAID(s) reaction sex/age intolerance b which triggered urticaria the reaction Multiple Facial 1/F/28 R, A - SR - + 120 mg NSAIDs urticaria mefenamic 2/F/35 R - CR Facial edema + + 30 mg - All patients acid were given Periorbital 3/M/44 - - ketoprofen SR - + 120 mg antihistamines edema - None needed -Periorbital resuscitation edema or epinephrine -Dizziness administration for <10 Multiple - Reaction 4/M/49 R, AD + CR seconds - + 30 mg NSAIDs resolved -No evidence within 4 hours of cardio- pulmonary compromise Abbreviations: A, asthma; AD, Atopic dermatitis; OPT, oral provocation test; R, rhinitis #Drug pattern: A single-reactor (SR) is defined as a patient with clinical reaction to only one type of NSAID, while a cross-reactor (CR), to more than one type of NSAID, including acetaminophen. Etoricoxib was tolerated by 70 (95%) of our while 1 had both cutaneous and respiratory symptoms. patients. The 4 subjects who reacted to the Furthermore, of the 121 subjects available for provocation test only had mild reactions consisting follow-up, 52 patients took etoricoxib subsequently, of periorbital and facial edema, urticaria and with only 2 patients having reactions, characterized transient giddiness. All these resolved with as very mild lip swelling that resolved antihistamines. There were no subjects needing spontaneously. The tolerability rate of this study was resuscitation or epinephrine administration. Table 2 comparable to the study done by Quercia. 6,7 shows the clinical characteristics of these patients. Our findings showed similar rates when We have shown that etoricoxib is a safe compared with these 2 studies. The tolerability rate alternative in NSAID intolerant subjects. In a study in our study may have been higher had our maximal done by Quercia et al.