Over the last century, there has been astounding progress in medical science, leading to the development of efficient, effective medications for treating cancer and a wide variety of other diseases. But the random dispersion of drugs throughout the body often lowers their effectiveness and, even worse, damages healthy tissue. A prime example of this is the use of chemotherapy drugs, which work to block cell division, causing hair loss and bowel issues in cancer patients (hair growth and waste elimination both depend on rapid cell turnover).