The aim of this study was to evaluate the canine blood and urinary profiles after envenomation by Tityus serrulatus venom. Twelve dogs were randomly distributed into two equal groups. Control group animals received 0.5 mL phosphate buffered saline (PBS) injected subcutaneously into the internal portion of the left thigh, whilst dogs in the envenomed group were injected with scorpion venom (250 μg/kg in 0.5 mL PBS). No significant alterations were detected in the urine of envenomed dogs. Levels of plasma glucose and serum urea, creatinine, total protein, potassium, alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine kinase (CK), lactate dehydrogenase (LDH), and amylase were determined. Semi-quantitative analysis of serum cardiac troponin I (cTnI) was performed using an immunochromatographic test. The concentrations of cortisol and insulin were determined using commercial radioimmunoassay kits. Increases in serum cortisol levels in experimental group animals coincided with hyperglycaemia and was probably a response to pain. Increased insulin levels were observed during the hyperglycaemic peaks. Envenomed dogs presented discreet increases in ALT, AST and CK, but no alterations in LDH, amylase, cTnI, urea, creatinine and potassium levels were observed. It was concluded that the venom of T. serrulatus induces blood and urinary biochemical changes in dogs. © 2010 Elsevier Ltd. All rights reserved.