A study was performed to evaluate the clinical and bacteriological efficacy of Cephalexin tablets on dogs which were diagnosed with a lower urinary tract infections (UTI) clinically diagnosed and confirmed by positive cyto bacteriological urine examination (CBUE) on D0 (bacterial counts >1,000 CFU/ml for cystocentesis, >10,000 CFU/ml for urethral catheterisation, >100,000 CFU/ml for palpation-pressure). Cephalexin-based tablets (Rilexine®, Virbac) administered at a dosage of 15 mg/kg twice daily for 10 days were compared to Amoxicillin-Clavulanic acid (ACA) tablets (Synulox®, Pfizer) administered at a dosage of 12.5 mg/kg twice daily for 10 days. Dogs were examined on 3 days: D0, D7 and D14 (5 days after the end of treatment). At each visit, a total clinical score (CS) was calculated by adding the severity scores of 11 clinical signs. On D10, a second urine sample for CBUE was performed. Efficacy of each product was assessed by the percent bacteriological recovery calculated on D10 (bacterial counts lower than the reference threshold value of the urine sampling method) and the percent reduction of the CS on D14.