Have you heard of denatured alcohol or Bitrex? Denatured alcohol, also known as alcohol denat, is ethanol that has been modified with additives, such as Bitrex, to make it unfit for human consumption. The primary reason for denaturing ethanol is to exempt it from taxes on consumable alcohol and to control its application in various industries. Bitrex, recognized for its extremely bitter taste, is one of the primary denaturants used in completely denatured alcohol, often referred to as Euro denatured alcohol.