臨床で併用されるカンレノ酸カリウム（ソルダクトン）の配合変化

We examined the compatibility of a commercialized potassium canrenoate preparation (Soldactone®) with 124 other kinds of currently prescribed injectable preparations as counter substances based upon the physicochemical parameters : actually, the appearance, pH, and the concentration of canrenoate were used as markers after mixing for 24 hours with other injectable preparations, since appearances can be deceptive. In order to estimate the remaining content of canrenoate after mixing, the concentrations of canrenoate were determined by UV absorption at the wavelength of 293 nm, using a spectrophotometer and reversed phase high-performance liquid chromatography (HPLC).As the results, no change was detected in 53 of the 124 counter preparations in the mixture and the content of canrenoate was above 90%. Sixteen total parenteral nutrition solutions, 5 amino acid solutions and 17 antibiotics dissolved in saline were incompatible with canrenoate.We also examined the compatibility of canrenoate, which was directly added to furosemide (20mg and 100 mg) and 5 % of glucose preparations. In the case of a furosemide injection (20mg), the appearance, pH and turbidity did not change, while the concentration of canrenoate decreased to less than 90% of the control. On the other hand, a glucose preparation (5 %) did not show any incompatibility with the counter preparations. Therefore, the canrenoate preparations can be dissolved into 5 % glucose solution, prior to the clinical application.