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Your body needs fluid (water) to work as it should. When you don’t have enough, it is called dehydration and it can cause several unpleasant, or even dangerous, symptoms. Having the right amount of fluid for your body to work correctly is called being hydrated.
You can become dehydrated because you don’t eat or drink enough or because you are losing too much fluid. People with cancer also can become dehydrated for many reasons such as:
Some people with cancer may be more likely to become dehydrated for other reasons:
It’s not always easy to know if you are dehydrated. Here are some of the common symptoms of dehydration.
If it is severe or untreated, dehydration can lead to low blood pressure, confusion, sleepiness, damage to the kidneys and liver, and even death.
For most people, dehydration can be prevented and treated by drinking more fluids. Your cancer care team might suggest an oral rehydration drink to help replace fluids, sugar, and electrolytes.
For people who can’t take in enough fluid by mouth, the cancer care team may order fluids given into a vein (IV fluids).
Your cancer care team will want to find out why you are dehydrated and treat that problem. This includes any symptoms or side effects that make it hard for you to get enough fluids. For example, nausea, vomiting, diarrhea, and trouble swallowing can make it harder to get or keep enough fluids in your body.
Fluids are in both food and drink. So, if you aren’t eating enough, you need to drink more fluids to make up the difference. You can do many of the same things to prevent and treat dehydration.
Developed by the American Cancer Society medical and editorial content team with medical review and contribution by the American Society of Clinical Oncology (ASCO).
American Society of Clinical Oncology. Dehydration. Cancer.net. Accessed on February 16, 2024.
Bethancourt HJ, Kenney WL, Almeida DM, Rosinger AY. Cognitive performance in relation to hydration status and water intake among older adults, NHANES 2011-2014. Eur J Nutr. 2020;59(7):3133-3148.
Sterns RH. Etiology, clinical manifestations, and diagnosis of volume depletion in adults. In, UpToDate, Emmett M (Ed), UpToDate. Accessed at uptodate.com on February 16, 2024.
Sterns RH. Maintenance and replacement fluid therapy in adults. In, UpToDate, Emmett M (Ed), UpToDate. Accessed at uptodate.com on February 16, 2024.
Taylor K, Jones EB. Adult Dehydration. [Updated 2022 Oct 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Accessed at https://www.ncbi.nlm.nih.gov/books/NBK555956/ on April 3, 2024.
Last Revised: June 26, 2024
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