US Patent 7498312 Compositions containing piperacillin and tazobactam useful for injection

An aminocarboxylic acid chelating agent, preferably EDTA, or a salt thereof has been found to be useful for inhibiting particulate formation in piperacillin/tazobactam parenteral combinations. The composition may also contain a buffer, preferably citrate, and optionally an aminoglycoside. The product may be in the form of a frozen composition that can be thawed for use. The product may also be in the form of a cryodesiccated powder that can be reconstituted by addition of an aqueous vehicle to reform a solution.