Challenge test to bisphosphonates in patients with hypersensitivity reactions to drugs.

reactionsAbstractBackground: Bisphosphonates are a commonly used class of drugs with known efficacy in theprevention and treatment of postmenopausal and steroid-induced osteoporosis, Paget’s dis-ease of bone, hypercaelcemia of malignancy, osteolytic lesions of multiple myeloma, and bonemetastases. Nitrogen-containing bisphosphonates have a favourable tolerability and safety pro-file, cutaneous reactions have been reported.Methods: This is a retrospective case series study, based on the analysis of data from 1429patients admitted to the Allergy and Clinical Immunology Division of the University of Messinabetween January 2011 and December 2012. Most patients had previous adverse drug reactions(ADRs) and referred to us for a challenge test with an alternative drug.Results: We observed six patients with a past history of adverse drug reaction who neededto be tested for bisphosphonates: three patients for risedronate, two for clodronate and onefor alendronate. In two years only two patients were referred to us for an adverse reactionto bisphosphonates: one to alendronate and one to risedronate. Another patient presented aprevious reaction to strontium ranelate. The other three patients reported previous hypersen-sitivity reactions to at least two different classes of drugs. All the patients experienced noreaction using the tested drugs.Conclusions: In our experience drug challenge tests for bisphosphonates are safe and reliable.