Drug action in biological systems is a subject of research as they exert their action by the interactions with different bio-macromolecules. Drug-macromolecular interactions involved in different physiological phenomenon, such as drug transport and anaesthesia. These interactions are generally complex in nature and therefore difficult to understand. Physico-chemical and thermodynamic studies provide information regarding the pattern of drug-macromolecular aggregation. Most of the biochemical processes is temperature dependant and occurs in aqueous media. Therefore thermo physical properties of drug-macromolecular systems in aqueous media at different temperatures provide valuable information in medicinal chemistry. Generally drug molecules contains both hydrophilic and hydrophobic groups hence it exhibits a number of specific and non specific interactions in aqueous media. Volumetric, viscometric and acoustic properties are helpful in understanding these interactions