The stability of cefodizime in five intravenous infusion fluids (0.9% sodium chloride, 5% dextrose in water, 10% dextrose in water, 5% amino acid injection, 3% polygeline) was studied at room temperature and at 4 degrees C. The compatibility of cefodizime with commonly used injectable drugs (ranitidine, metoclopramide, folinic acid, furosemide, aminophilline, methylprednisolone, betamethasone, hydrocortisone, dexamethasone, ketoprofen, noramidopyrine, acetylcysteine, digoxin, diazepam, acetylsalicylic acid, chlorpromazine, clonidine, clomipramine) was studied in 0.9% sodium chloride and 5% dextrose at room temperature. At intervals during the storage periods (up to 24 hrs at room temperature; up to 6 days at 4 degrees C) color, clarity and solution pH were examined; cefodizime content was determined by a microbiological method. Cefodizime concentrations remained greater than 90% of the initial concentrations in all infusion fluids for at least 24 hrs at room temperature and 6 days at 4 degrees C. No visual changes or appreciable changes in pH were observed for any of the solutions. Immediate clouding was observed when chlorpromazine was combined with the solution of cefodizime. A color change was observed when acetylcysteine was mixed with cefodizime. An increase in pH was noted when aminophilline was added to the solution of cefodizime. However, cefodizime concentrations remained greater than 90% of the initial concentrations of the solutions after mixture with all the tested drugs for at least 24 hrs at room temperature.(ABSTRACT TRUNCATED AT 250 WORDS)