Background Sitagliptin is a selective dipeptidylpeptidase 4 inhibitor indicated for the treatment of Type II diabetes mellitus. Diabetics gefitinib lung treated with sitagliptin develop upper respiratory tract infections. cough. and sore throat in 5% to 6% of subjects. Similar rates for these adverse events have been reported for the other DPP IV inhibitors vidagliptin and saxa gliptin. Infections from all causes had a 34% relative risk increase for sitagliptin compared to other diabetes treat ments. Previous studies have predicted that airway adverse events may occur with this class of drugs. We propose that inflammatory changes Inhibitors,Modulators,Libraries may be occurring that were coded as infections in clinical studies. This is of importance in balancing the risk benefit ratio for treat ment with DPP IV inhibitors.

Two subjects who had recently started taking sitagliptin presented to our clinics with rhinorrhea, cough, dyspnea and fatigue, and requested evaluations for drug sensitiv ity. We challenged these index cases to determine if sita gliptin Inhibitors,Modulators,Libraries induced a reproducible syndrome. When the challenges were affirmative, we reviewed charts to iden tify other sitagliptin treated subjects. We identified sita gliptin intolerant and tolerant groups, and began an analysis of potential mechanism and risk factors for this new drug induced syndrome. Methods The index cases were type II diabetic subjects who pre sented to an urban tertiary allergy center and a rural fam ily practice clinic with upper andor lower airway symptoms shortly after starting oral sitagliptin.

Chart reviews at the rural clinic identified 205 diabetics including 31 who had received sitagliptin as an adjunct to combinations of met formin, sulfonylurea and insulin. Symptoms Inhibitors,Modulators,Libraries of fatigue, anterior and posterior rhinorrhea, cough, and sensations of wheezing or dyspnea defined a sitagliptin intolerant population. Fifteen intolerant and seventeen tolerant patients were identified and examined for potential risk factors and mechanisms of sitagliptin related com plaints. Outpatient evaluations included history, review of medication related adverse events, physical examina tion, and, when possible, measurement of peak expiratory flow rates. Spirometry and allergy skin tests were per formed at the urban clinic.

Peak expiratory flow rate and Inhibitors,Modulators,Libraries subjective impressions of anterior and poste rior nasal discharge, cough, dyspnea, and fatigue symp toms scores were assessed by the physician at the visit when sitagliptin was stopped, and by the patient for a 1 to 2 week follow up period. Health insurance restrictions and referral opportunities precluded allergy testing for most Inhibitors,Modulators,Libraries of rural diabetics. Clinical diagnoses of allergic rhinitis and asthma were inferred from Allergic Rhinitis In Asthma and Global activator Ivacaftor Initiative for Asthma guidelines. Specific details are given in the Case Reports. The diagnosis of allergic rhinitis was made clinically using the symptom algorithm of the ARIA guidelines.