Acute interstitial nephritis induced by loratadine

Loratadine is a second generation histamine H1 receptor antagonist, that has high potency antiallergic properties and is associated with low adverse effects compared with other antihistamines. Acute interstitial nephritis is a cause of acute renal failure that is most often induced by drugs or, less frequently, infection or sarcoidosis. Although the number of drugs associated with acute intersticial nephritis is too large, the antihistaminic loratadine have never been reported before. We report a case of an interstitial nephritis with acute renal failure that suggesting hypersensitivity reaction in a 77 old man who had received loratadine (10 mg/day) during ten days before his assesment to our hospital by diseminated pruritic syndrome. The initial suspect was rapidly progressive glomerulonephitis and renal biopsy was practice and treatment with corticosteroids were initiated (prednisone bolus of 500 mg three days and 1 mg/kg/day/later). The loratadine therapy was cessation. He exhibiting a slow and progressive improvement on renal function and one month later, urea and creatinine levels was normal and hematuria and proteinuria had disapeared. The corticosteroids therapy were progressive decreased until withdrawal. We think that this is an interesting case, basing in its clinical presentation and that it had never been reported before.