The object of the invention is a composition, particularly a pharmaceutical composition, in the form of a liquid preparation, which - in combination and in active, particularly pharmaceutically effective quantities - comprises (a) triclosane, and (b) at least one polyol. The composition according to the present invention is preferably suitable for the use as a blocking agent (blocking substance) for catheters, particularly urinary bladder catheters, wherein it counteracts particularly incrustations in long-term catheterizations.
