Sitagliptin adverse events. The presence of allergic rhinitis (AR) and its treatment (AR Rx), ACE inhibitor intolerance (ACE intol.), duration of sitagliptin treatment before symptoms began, the nature of the symptoms, and effects of discontinuation and subsequent challenge are shown. PEFR values are shown as % change after stopping sitagliptin, or normalized % of predicted (% pred) for tolerant subjects. Five subjects had restrictive patterns on spirometry that may have been related to obesity. Their PEFRs were not reported. Effective use of intranasal and inhaled corticosteroids (INS+ICS) prevented the return of symptoms for Case 5. Cases 16 and 18 used chronic methotrexate for rheumatoid arthritis (*). Case 23 developed a rash with sitagliptin which recurred on rechallenge. Case 9 now requires hemodialysis for hypertensive renal failure. Case 25 developed non Hodgkins lymphoma. Case 7 died from a pulmonary embolism. Case 24 had a sudden unexpected death. (nil, no complaints; n.d., not determined).