For many mesothelioma patients, the administration of cytotoxic (chemotherapeutic) agents is a critical component of their curative or palliative treatment. Cytotoxic therapies are an important weapon in the oncologist’s arsenal of cancer treatment, but they often cause unpleasant and even dangerous side effects.
Today, new forms of cytotoxic agents appropriate for some forms of cancer, as well as advanced drugs that effectively suppress their unwanted side-effects, combine to provide cancer patients with a far more comfortable course of chemotherapy-based treatments. Ask your doctor for more information.
Nausea, Vomiting, and Signals from the Brain
Nausea and vomiting-what causes it? All bodily functions, in one way or another, are inevitably controlled by the brain, and stomach upset and vomiting are no exception. The action of vomiting is regulated by a specific location within the brain that is commonly known as the vomiting center. This cerebral site is found on the floor of the fourth ventricle of the brain, a location also known as the area postrema, a neurological center characterized by clusters of receptor cells that, when stimulated, cause nausea and vomiting. The area postrema is also known as a circumventricular organ because it is external the blood brain barrier, which means it can receive stimulation from, among other things, blood-borne cytotoxic agents. In addition to stimulation from chemotherapies, the area postrema can also react unfavorably (induce vomiting) as a result of signals from additional anatomical sites such as those noted below:
- The cerebral chemoreceptive trigger zone (CTZ) that is stimulated by foreign substances, drugs or chemicals in the bloodstream
- Digestive tract organs and nerves that react to chemotherapeutic irritation or disease
- Cerebral cortex and limbic system receptor sites that react to odors, taste sensations, sight, pain, and emotional discomfort
- Inner ear receptors that respond to motion
Vomiting center stimulations and reactions occur when receptor cells interact with chemical compositions known as neurotransmitters, which arrive at the area postrema carrying a variety of instructions to induce the different types of nausea and vomiting that are noted below:
- Breakthrough vomiting-chronic nausea and vomiting that persists despite the administration of antiemetic (anti-nausea) drugs or other therapies
- Acute nausea and vomiting-this describes stomach upset and vomiting that presents within a few hours of the delivery of chemotherapies
- Delayed nausea and vomiting-this side-effect typically presents 24 hours or more subsequent to the administration of chemotherapies
- Anticipatory vomiting-this is a learned behavior that causes the onset of nausea and vomiting just prior to the administration of chemotherapies
- Increased Risks for Chemotherapy Related Nausea and Vomiting
There are a number of factors that can increase the likelihood of experiencing nausea and vomiting as a result of chemotherapy treatments. Some cancer-fighting drugs carry a higher risk of stomach upset and vomiting than others: the chemotherapy drugs Adriamycin (doxorubicin) and Platinol (cisplatin), for example, are associated with over a 90 percent risk of nausea and vomiting, while Methotrexate or Navelbine (vinorelbine) cause the unwanted side-effect in less than 10 percent of cancer patients. Some of the other factors that can increase the risk for chemotherapy-caused nausea and vomiting are noted below:
- Female patients are at higher risk
- If you are under age 50
- Receiving very high dosages of chemotherapy
- Abstinence from alcohol
- Receiving chemotherapies intravenously as opposed to by mouth
- Increased frequency of treatments-less recovery time
- A past history of motion sickness
- New Antiemetic Drugs Provide Relief for Many
While moderate to severe digestive tract discomfort and vomiting was long the norm for many cancer patients who received chemotherapies, this is no longer the case. Several new anti-nausea drugs provide cancer patients with relief from the stomach upset and vomiting caused by chemotherapy, and as an added benefit of these substances, physicians are able to provide their patients with significantly higher doses of cancer-fighting agents. Most antiemetics achieve their results by blocking nausea-causing signals to receptor cells in the brain’s vomiting center. One class of these highly effective antiemetics is known as 5HT3 antagonists, which include Anzemet (dolasetron), Kytril (granisetron), and Zofran (ondansetron). Two additional drugs that are part of a second generation of 5HT3 antagonists are Emend (aprepitant) and Aloxi (palanosetron), both of which are administered intravenously. A third drug in this same class is the antiemetic Sancuso (granisetron), which delivers its relief in time released dosages through a skin patch.
More on Side Effects
Peripeheal Neuropathy as a side effect of chemotherapy
Eye problems in chemotherapy patients
Neuropathy and the mesothelioma patient
Anti-nausea treatment for chemotherapy patients
Shingles in cancer patients
Anemia from chemotherapy
Mouth sores as a side effect of chemotherapy
Hair loss as a side effect of chemotherapy
More on nausea and vomiting from chemotherapy
Managing chemotherapy side effects
Hepatotoxicity from chemotherapy treatment
Nadir of chemotherapy
