The aqueous injection solution comprising an LHRH antagonist contains in addition to the LHRH antagonist, such as cetrorelix, an organic, physiologically compatible acid and optionally a surfactant and also a framework builder. The LHRH antagonist has significantly improved solubility and can be prepared in higher concentrations and with an improved bioavailability. The aggregation tendency of the LHRH antagonist is significantly reduced.
