The history of chemotherapy traces back to medical observations in World War I. Soldiers who were exposed to chemical warfare, Sulfur Mustard, suffered from the lowering of their white blood cells, especially lymphocytes. Following that observation, Nitrogen Mustard, a similar and yet less toxic agent, was used in patients with high white blood cells (lymphoid leukemia) and then in lymphomas. Nitrogen Mustard indeed lowered the count of lymphocytes and assisted in the management of lymphoid cancers. Today, this drug still plays a major role in the treatment of Hodgkin's Disease.
If one is considering chemotherapy for treating cancer, there are always possible adverse effects in undergoing this procedure. Although chemotherapy is relatively simple and painless, it has risks. The most common side effects of chemotherapy include neutropenia (a low white blood cell count), anemia (a low red blood cell count), thrombocytopenia (a low blood platelet count), depression, hair loss, nausea, and vomiting.
Some people never experience nausea or vomiting. Others are nauseated every day of treatment. Many people describe having “stomach awareness” --- a condition when loses appetite even if there are not symptoms of stomach discomfort or nausea. Some people have nausea that lingers for more than a week after a chemotherapy session. Thankfully, these side effects can almost always be controlled, or at least substantially reduced, by the use of a variety of drugs.
Antiemetic drugs act centrally on the gastrointestinal system to suppress symptoms of nausea. Drugs that act primarily on the central nervous system receptors or the vestibular system include butyrophenones (e.g., haloperidol), phenothiazines (e.g., prochlorperazine, chlorpromazine), antihistamines (e.g., cyclizine) and anticholinergics (e.g., hyoscine). Antiemetic drugs with direct effects on the gastrointestinal system include metoclopramide, domperidone and octreotide (an analog of somatostatin). Antagonists of 5-HT3 receptors (i.e., ondansetron and tropisetron) have both central and gastrointestinal effects, drugs that are considered to be effective but quite expensive. Specific medications should be selected to match the drug effect to the cause of the vomiting. Other matters to be considered in drug administration include the side-effect profile, route, timing, form of administration, cos of the drug, and a variety of patient-specific factors.
Nausea makes a cancer patient experience anxiety, making their discomfort more pronounced. The normal uncertainty and worries that accompany the first chemotherapy session adds to the difficulty experienced by a cancer patient. The same emotional factors that can cause nausea before a test or seeing a doctor can also lead to more nausea before chemotherapy. Plus, anxiety can cause indigestion and heartburn, which can make matters worse. Constipations and coughing due to bronchitis or a bad cold can also contribute to nausea. Sometimes, nausea can also be a side effect of pain medications.
Nausea and vomiting are common side effects of chemotherapy treatment for cancer. But they aren't inevitable. There are newer nausea and vomiting treatments that can help prevent these side effects. The doctor and patient can take steps to prevent or decrease nausea and vomiting associated with chemotherapy and to make the patient more comfortable during the cancer treatment.
The side effects of chemotherapy come about because cancer cells aren't the only rapidly dividing cells in the body. The cells in the blood, mouth, intestinal tract, nose, nails, vagina, and hair are also undergoing constant, rapid division. This means that the chemotherapy is going to affect them too. Before chemotherapy starts, it's important to understand nausea and all the factors that can affect it. By being informed and working closely with a health care team, perhaps one can avoid nausea and vomiting entirely --- making the process of beating cancer less difficult for a patient to endure.
