geous to have admixed with said solid cephalosporin as a stabilizing and/or solubilizing agent a sterile, anhydrous solid such as sodium carbonate, potassium carbonate or lithium carbonate (e.g. in about 5 or 6 percentby weight of the weight of the cephalosporin) or such as L-lysine, arginine or histidine (e.g. in about 20-50% by weight of the weight of the cephalosporin) or such as a sod