Chemotherapy is the use of chemicals to treat cancer. Chemotherapy is also known as “chemo”. The term chemotherapy came from German bacteriologist Paul Ehrlich around 1900. He coined the term while examining aniline dyes and arsenical as possible treatments for diseases such as syphilis. He envisioned “magic bullets” that would be able to target invading organisms while still leaving the host unharmed. This goal has been to provide therapeutic benefits without many side effects in all areas of drug development. There has been a lot of success with compounds that modulate normal biochemistry within the body. Chemotherapy is used for many different things. Chemo can be used to stop cancer from spreading, slow cancer growth, kill cancer cells that have already spread to other parts of the body, relieve symptoms such as cancer pain, shrink tumors, and of course, to cure cancer. Chemo can be given in many different ways. It can be administered by injection, through an IV, topically, directly into the body cavity, and orally. Oral chemotherapy is given as a liquid, tablet, or capsule that you swallow. Oral chemo is not as effective as other forms, but it can work just as well. Chemotherapy given through an IV is the most common. The side effects caused by chemotherapy are very serious for the body. These side effects occur because chemotherapy agents are toxic and cancer cells and normal cells are very similar, so it is very difficult to leave normal cells unharmed while causing the patient to experience side effects during chemo. These side effects may include nausea, vomiting, diarrhea, hair loss, mouth sores, skin changes, and low blood counts. These side effects do not… half of the article… this is also part of a series called pharmacodynamics. This includes both positive and negative changes made by a drug. This study is important because when a drug is administered it must reach its target in the body before being excreted or altered by the body's detoxifying enzymes. Most of these enzymes are found in the liver. The results of these tests have enabled the synthesis of new drugs with improved chemical characteristics, distributions and toxicity profiles. Specificity is a common thing in the world of chemo. There have been many drugs that have shown specificity for certain tumors. Knowing why a drug exhibits specificity is not usually obvious. The specificity of a given drug is usually discovered through trial and error. They still don't know why exactly the specificity occurs, but it appears to arise from the different biochemistry of the tumor cells.