Infusion of ciprofloxacin having reduced acid content and being stable in storage

The invention relates to aqueous infusion solutions of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-quinoline-3-carboxylic acid (ciprofloxacin) which are stable in storage and which can be obtained by mixing between 0.015 and 0.5 g of active ingredient for 100 ml of aqueous solution with sulphuric acid or sodium hydrogen sulfate in a quantity equal to or less than 0.96 mole per mole of active ingredient, sufficient for dissolving the active ingredient and stabilizing the solution. The invention also relates to methods for producing the infusions and the use thereof. The inventive infusions enable the acid content to be reduced, are more stable in storage with the same acid content than other known solutions, and enable a larger proportion of secondary components to be tolerated in the active ingredient than previous standard infusions of ciprofloxacins.