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Nausea can be described as having a sick or uncomfortable feeling in the back of your throat and stomach. There are many other words describing the feeling of nausea, including "sick to one's stomach", "queasy", or "upset stomach". Other symptoms can happen at the same time as nausea, such as increased saliva (spit), dizziness, light-headedness, trouble swallowing, skin temperature changes, and a fast heart rate.
Vomiting is also described as “throwing up.” Nausea can lead to vomiting, and sometimes nausea and vomiting happen at the same time, but they can be totally separate problems, too. When you vomit, your stomach muscles contract (squeeze) and push the contents of your stomach (liquids and food) out through your mouth.
Retching is when your body tries to vomit without bringing anything up from your stomach. Other words used to describe retching are gagging or having the dry heaves.
Nausea and/or vomiting in the person with cancer can be caused by many different things, such as:
Not all people who get cancer treatments have nausea and/or vomiting. Your risk for having nausea or vomiting depends on the type of cancer being treated and the type and dose of treatment being given.
Chemotherapy and other drugs used to treat cancer travel throughout the body while radiation therapy treats one part of the body where the cancer is located. For this reason, chemotherapy and some other drugs used for cancer treatment cause more nausea and vomiting than radiation therapy. If you are getting chemotherapy, you might hear your cancer care team refer to it as chemotherapy-induced nausea and vomiting (CINV). Your cancer care team knows which treatments have a higher risk for CINV because studies have shown that certain drugs used to treat cancer are more likely to cause nausea and vomiting than other others. Chemo and other drugs used to treat cancer are classified according to their emetogenic potential (how likely the drug will cause nausea or vomiting) as high, moderate, low, or minimal risk. Anti-nausea drugs are used to help control and even prevent nausea and vomiting depending on this risk. You may hear them called anti-emetics.
Every person with cancer who’s getting treatments that cause nausea or vomiting can, and should, get medicines to keep this from happening or to control it. Talk to your doctor for more information or if you have questions about your risk for nausea and vomiting.
The exact way that nausea and vomiting occur is still not fully understood, but studies have shown a pathway in the brain that is triggered and sends signals to make it happen. When you are given cancer treatment that can cause nausea:
Nausea and vomiting are some of the most unpleasant side effects of cancer treatment, but they have become less of a concern due to more effective treatment for them. They rarely become life-threatening.
Still, nausea and vomiting can make it hard to get the nutrition your body needs. Nausea can make you not want to eat or drink anything, and repeated vomiting can lead to dehydration, which is a lack of fluids and minerals your body needs. If nausea and vomiting persist, they can quickly become a serious problem. Be sure to let your cancer care team know right away if either of these happen:
Vomiting can also cause tiredness (fatigue), trouble concentrating, slow wound healing, weight loss, and loss of appetite. It can interfere with your ability to take care of yourself and may lead to changes in your treatment plan.
Ask your cancer care team these questions:
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Blanchard EM, Hesketh PJ. Nausea and vomiting. In DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2019:2078-2085.
Brant JM, Stringer LH. Chemotherapy-Induced nausea and vomiting. In Brown CG, ed. A Guide to Oncology Symptom Management. 2nd ed. Pittsburgh, PA: Oncology Nursing Society; 2015:171-196.
Cancer.Net. Nausea and vomiting. 2018. Accessed at https://www.cancer.net/coping-with-cancer/physical-emotional-and-social-effects-cancer/managing -physical-side-effects/nausea-and-vomiting on September 5, 2019.
Hainsworth JD. Nausea and vomiting. In Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020: 599-606.e3.
National Cancer Institute (NIH). Treatment-related nausea and vomiting (PDQ®)- Health Professional Version. 2018. Accessed at https://www.cancer.gov/about-cancer-treatment/side-effects/nausea/nausea-hp-pdq on September 6, 2019.
Last Revised: February 1, 2020
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