The chemical stability of the cardioprotective agent ICRF-187 in 0.9% sodium chloride and 5% dextrose infusion fluids has been investigated. The admixtures (concentration: 10 mg/mL and 1 mg/mL) were stored in glass bottles or polyvinyl chloride containers at 4 degrees C in the dark and at room temperature (20-22 degrees C) both protected from light and under normal room fluorescent light conditions in a day-night rhythm. Samples withdrawn immediately after preparation and after 6 hours, 1, 2, 3 and 6 days were analyzed using high performance liquid chromatography with ultraviolet detection. Samples were also inspected for visual changes and tested for changes in pH. Chemical stability of ICRF-187 was also investigated as a function of pH (range 1-12) at room temperature. It is concluded that ICRF-187 is slightly more stable in 5% dextrose than in 0.9% sodium chloride infusion fluids. The stability of the drug is not influenced by normal room fluorescent light nor by the type of container material used. Precipitation occurred in both 5% dextrose and 0.9% sodium chloride with a drug concentration of 10 mg/mL and storage in the refrigerator at 4 degrees C. The chemical stability of ICRF-187 in aqueous solution is mainly a function of pH. At pH 1, no decomposition is detected within 24 hours, at pH 7, 35% decomposition occurs in 21 hours, while at pH 12 it degrades completely within 20.5 hours.