RESUMO
1. The metabolism of the erythrocytes in the gentian violet (GV)-treated blood from ten donors was studied weekly from time zero to the 28th day of storage in order to evaluate the efficacy of the use of GV in the chemoprophylaxis of transfusional Chagas' disease. 2. Adenosine triphosphate (ATP) levels in erythrocytes of GV-treated blood were similar to the control until and including the 21st day, with a significant decrease of approximately 40% in relation to control detected only on the 28th day. 2,3-Diphosphoglycerate levels of GV-treated blood significantly decreased from the 21st to the 28th day in relation to the control. However, they were above the minimum accepted for good preservation. pH, partial oxygen pressure (pO2), partial carbon dioxide pressure (pCO2), sodium and potassium levels were similar to the respective controls. 3. The use of gentian violet in the chemoprophylaxis of transfusional Chagas' disease is strongly recommended in endemic areas and/or where no safe serologic tests are available.