In the early 1980s synthetic ‘human’ insulin produced by recombinant DNA technology came onto the market. Despite an acknowledgment by the manufacturers regarding the potential dangers of ‘human’ insulin they soon began to withdraw bovine and porcine insulin from markets all over the world, and promoted more expensive ‘human’ insulins as a superior replacement. Diabetics had no option but to effectively switch to the new synthetic insulins and often they received little or no information about their potentially life-threatening side effects. In the first part of this book the author provides fundamental information about insulin therapy and its history. A detailed discussion of the hazards confronting some diabetic patients when using ‘human’ insulin follows. Due to more pronounced hypoglycemia symptoms animal insulin can be regarded as safer than ‘human’ insulin for 10-20% of diabetic patients. The last part of this publication looks at the pharmaceutical industry’s decision to withdraw animal insulin from the market and describes the struggles of a new global movement to secure its continued availability. This book not only provides potentially vital background information for those who depend on insulin, but also deserves the attention of professionals who prescribe or distribute this medication. It can also serve as a reference for patient advocates, relevant government departments and pharmaceutical companies.