Every year, more than 1 million people in the United States alone receive chemotherapy. Although it helps hundreds of thousands of people survive cancer, most patients dread the thought of undergoing these treatments-not because they think they will not cure the cancer but because of the severity of the negative side effects. At the mere mention of the word chemotherapy, patients often envision themselves bald, exhausted, and vomiting, unable to concentrate and almost more sick from the hemotherapy than from the cancer.

On a basic level, chemotherapy is the very careful administration of poisons to kill cells. Most of the drugs used for chemotherapy are cytotoxic, meaning they have the potential to kill any cell. As one would expect, this poison sometimes goes out of control. Doctors can trace the causes of the most common side effects of chemotherapy directly to unintentional results...