The choice of solution for the initial infusion therapy to restore the volume of circulating blood (CBV) has been a subject of debate for many years. The purpose of our study was to compare the effect of different routes of administration of infusion solutions on CBV. The study was conducted on 250 rats weighing 200-260 g and aged 3-4 months. Animals were born from different females. The dynamics of the neutral red concentration in the gastric perfusate were measured using a 0.9% sodium chloride solution and a 10% albumin solution, which were administered in three different ways. It was established that the intravenous administration of a 0.9% sodium chloride solution at the 60th minute of the experiment reduced the concentration of an aqueous solution of neutral red in the gastric perfusate by 35%, and a 10% albumin solution by 22% compared to the control. This indicates an increase in CBV. When a 0.9% solution of sodium chloride was administered intraosseously, the concentration of an aqueous solution of neutral red significantly decreased by 33% at the 45th minute and by 44% at the 60th minute. On the other hand, under the influence of 10% albumin solution, CBV decreased by 22% at the 45th minute and by 41% at the 60th minute, but not significantly compared to the control. Therefore, the use of these solutions causes an increase in CBV in experimental animals both when administered intravenously and intraosseously, that is, it has similar hemodynamic effects. The retroperitoneal route of administration did not affect CBV changes.