The term “hydrotropy” has been used to designate the increase in solubility in water of certain substances due to the presence of large amounts of additives. This phenomenon is more closely related to complexation involving a weak interaction between the hydrotrophic agent and the solute. This phenomenon is also due to the change in the solvent character because of the large amount of additive needed to bring about the increase in solubility. Examples of hydrotropic agents are sodium benzoate, urea, sodium acetate, polyvinyl pyrrolidone and sodium salicylate.