Diabetic nephropathy is an unmet therapeutic need, and the search for new therapeutic strategies is warranted. Previous data point to histamine H 1 receptor as a possible target for glomerular dysfunction associated with long term hyperglycaemia. Therefore, this study investigated the effects of the H 1 receptor antagonist bilastine on renal morphology and function in a murine model of streptozotocin-induced diabetes. Diabetes was induced in DBA2/J male mice and, from diabetes onset (glycaemia ≥200 mg/dL), mice received bilastine (1–30 mg/kg/day) by oral gavage for 14 consecutive weeks. At the end of the experimental protocol, diabetic mice showed polyuria (+195.5%), increase in Albumin-to-Creatine Ratio (ACR, +284.7%), and a significant drop in creatinine clearance ( p < 0.05). Bilastine prevented ACR increase and restored creatinine clearance in a dose-dependent manner, suggesting a positive effect on glomerular filtration. The ultrastructural analysis showed a preserved junctional integrity. Preservation of the basal nephrin, P-cadherin, and synaptopodin expression could explain this effect. In conclusion, the H 1 receptor could contribute to the glomerular damage occurring in diabetic nephropathy. Bilastine preserved the glomerular junctional integrity, leading to the hypothesis of anti-H 1 antihistamines as a possible add-on therapy for diabetic nephropathy.