The purpose of this study was to evaluate the safety and efficacy of the synthetic colloid hetastarch in dogs with hypoalbuminemia. Individual doses of hetastarch ranged from 9 to 27 mL/kg, and multiple doses were used frequently. Total doses ranged from 9 to 59 mL/kg. Colloid oncotic pressure was measured in 13 dogs before and after treatment. Mean colloid oncotic pressure ± SD was 9.32 ± 2.35 mm Hg before treatment and 16.41 ±1.61 mm Hg in 8 healthy pet dogs used as controls. The difference in these values was significant (P < .001). There was a significant increase in mean colloid oncotic pressure after the first dose of hetastarch, but there was no relationship between the dose of hetastarch and the magnitude of increase in colloid oncotic pressure. Peripheral edema or body cavity transudates resolved or decreased in 83% of the dogs despite concurrent use of crystalloid fluid therapy. There was also no relationship between the dose of hetastarch and resolution of edema. Worsening of the results from coagulograms occurred in 5 of 18 dogs, and included increased prothrombin time (n = 1), increased partial thromboplastin time (n = 5), and decreased platelet count (n = 3). Bleeding that occurred in 3 dogs could not be directly attributed to the hetastarch. There was no relationship between the dose of hetastarch and worsening of the values in the coagulograms.