This article describes the rheological properties of certain poly(ethylene oxide)s dissolved in water-based solvents. The experimental results show that the rheological properties in aqueous solutions are significantly affected by the solvent properties, which have been changed by the use of ethanol-water mixtures and electrolyte solutions and by the variation of the ambient pressure and temperature. The variation of the temperature and pressure is seen to change the polymer chain configuration and also the interactions of polymer segments with the solvent molecules. This gives rise to distinctive and apparently unusual rheological properties for these systems with the variation of the ambient temperature and pressure. The study generally illustrates that the rheology of these systems are, to a large degree, influenced by the hydrogen bonding in the solvent and between the solvent as well as the polymer. At a first-order level, the increase of the pressure and the temperature and also the addition of electrolytes, and the inclusion of an aqueous diluent, produce comparable effects. In essence, these changes seem to disrupt the hydrogen bonding structure in the solutions and, hence, the solvent quality in a comparable fashion.