He therefore has to be educated on how the process of chemotherapy takes place and the importance of maintaining good oral hygiene. Even though John follows all the advice from the doctors, he still developed ulcers in his mouth due to chemotherapy. In response to these side effects, the nurses intervene to prevent the worsening of the side effects. Side effects of fluorouracil Fluorouracil is, a drug used in the treatment of cancer. It performs by making an irremediable reserve of thymidylate synthase. It interrupts the action of enzyme blocks hence hinders synthesis of pyrimidine thymidine which is a nucleoside for DNA replication (Winawer et al, 2003). Chemotherapy is generally used to kill any rapidly growing cells in the body thus killing the cancerous cells (De vita, 2001). Such rapidly multiplying cells are found in the mouth linings hence they fall victims to this chemicals. The reaction between the healthy cells in the mouth linings and the fluorouracil leads to formation of sores and ulcers. Since the occurrences of sores are hard to prevent, the extent of damage caused by the sores can be limited. In order to counter the side effects of chemotherapy, the patients need to be fully educated on the importance of good oral hygiene. They should be encouraged to regularly brush their teeth in order to prevent accumulation of germs in the mouth. In addition, the nurses should intervene so that the patient is given good medical care. They should ensure that the patient gets full nutritional supplements and he/she is free from pain. Discussed below are importance of maintaining good oral hygiene and the nursing interventions of preventing the side effects:- Oral hygiene education as a method of preventing side effects of chemotherapy Oral hygiene entails keeping both mouth and teeth clean as a way of preventing bad breath and tooth decay. It not only involves brushing the teeth but also maintaining the whole mouth including the tongue, gum and the inner skin of the mouth. In the case study, John was constantly advised to have a good oral hygiene before going for the chemotherapy sessions. This is because; the cancer drugs contain some reactive chemicals, which are designed to kill any rapidly growing cells (Bradbury, 2007). In the process of eliminating the rapidly growing cells, these drugs encounter mouth cells that are also multiplying rapidly. The healthy cells in the mouth react with the chemical substances in the drugs hence resulting into a chemical reaction, which damages the skin of the mouth. This chemicals cause sores in the mouth and in the throat, a condition referred to as mucositis. The chemical substances in the drugs make the tissues dry, soft and easily irritable hence it may result to bleeding gums (Lewis, 2007). If oral hygiene were not maintained, the mouth germs would infect the sores. Such germs would lead to further complications for the patient because mouth infections would result to administering of other drugs, which may affect the functioning of the cancer drugs (Drasdo, 2001). In the case study, John is advised to brush his teeth regularly; due to the softness of his gums, he is told to be gentle while brushing and use a toothbrush with soft brittles. He is also advised to ensure the whole mouth including the tongue and the gums are properly cleaned. By ensuring good oral hygiene, there will be minimum damage on John’s mouth hence the worsening of the mouth sores would be curbed.