Abstract: An additive composition for boosting performance of water-based drilling fluids. Modified water-based drilling fluids including the additive composition. Methods of making the additive compositions. Methods of using the modified drilling fluids to drill or perform other operations in reactive shale formations. The additive compositions include one or more multi-hydroxyl alcohols, a lubricant mix, a shale inhibitor, a strong base to adjust pH, and optionally water up to about 20 percent by volume, based on total volume of the additive composition.