Allegra - I have chronic kidney disease. What are the issues with this drug and kidney disease?

In renal disease, if your creatinine clearance is low then drug level will be higher.

In renally impaired patients. In subjects with mild to moderate (creatinine clearance 41–80 mL/min) and severe (creatinine clearance 11–40 mL/min) renal impairment, peak plasma concentrations of fexofenadine were 87% and 111% greater, respectively, and mean elimination half-lives were 59% and 72% longer, respectively, than observed in healthy subjects. Peak plasma concentrations in subjects on dialysis (creatinine clearance ≤10 mL/min) were 82% greater and half-life was 31% longer than observed in healthy subjects. Based on increases in bioavailability and half-life, a dose of 60 mg once daily is recommended as the starting dose in adult patients with decreased renal function. For pediatric patients with decreased renal function, the recommended starting dose of fexofenadine is 30 mg once daily for patients 2 to 11 years of age and 15 mg once daily for patients 6 months to less than 2 years of age. (See DOSAGE AND ADMINISTRATION).

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