Chemotherapy dehydration can be life-threatening if left untreated. This article has simple tips to deal with and avoid becoming dehydrated. But first, we will start with....
What is chemotherapy dehydration?
It is a serious condition that can be life-threatening if left untreated and should not be taken lightly.
The excessive loss of body fluids, which is dehydration, occurs when your body’s fluid output exceeds its fluid intake. Vomiting or diarrhea, side effects of cancer treatments, can lead to dehydration, as can infections, high fever, bleeding or merely not drinking enough fluid.
Symptoms of dehydration and what to do
To tell if you are dehydrated lightly pinch and pull up your skin. If it stays standing up in a tent, this is a sign that you are dehydrated.
What are mild dehydration symptoms?
• sticky, dry mouth • feeling sleepy • getting thirsty • decreased urine output • few or no tears • headache • dizziness
What to do if  you have mild dehydration
• Don't drink a lot too much at once. Sip fluids slowly, gradually drinking more and more. • Suck on ice cubes to keep your lips and mouth moist. • Eat foods that have plenty of fluid, such as watermelon or cucumbers. • Use lip balm or salve if your lips are dry, and lotion on dry skin. • Fill a small cooler with clean ice and small bottles of fluid (water or juice) and keep it close by so you drink frequently.
Severe dehydration, a medical emergency and you need to talk to your doctor immediately if you have any of the symptoms of severe cancer dehydration.
Avoiding Cancer Dehydration And Staying Hydrated
The expert advice is to drink about 8-12 glasses of water a day. Even though this figure is disputed by some researchers, scientists agree that most people don't drink enough. So, in general, if people should aim to drink 8 glasses of water a day to not get dehydrated.
However, if you have cancer therapy side effects such as diarrhea or vomiting, you would need to drink more than 8 glasses of water a day to stay hydrated and avoid cancer dehydration.
Ways to make sure you stay hydrated include:-
Drink a lot.
Although it seems obvious it is not always easy to drink a lot if you feel sick. A lot of small sips can help and keeping a water bottle with you at all times is a good reminder to drink. Sucking on small pieces of ice works can help improve your fluid intake, but you will need a lot of ice.
If you dislike plain water you could try drinking flavored water or adding a slice of lemon to get enough fluids. Other fluids can also help, including milk, low-sugar juice, and caffeine-free tea.
Avoid caffeine
Yes you need to drink a lot, but only the right sort of fluids, water and juices are good but drinks with caffeine, such as coffee, tea and some fizzy drinks coke, acts as a diuretic. They will flush water out of your system which is the opposite of what you want to achieve.
Keep track of your fluid intake and output
It’s not easy to tell how much fluid you’re losing unless you measure it and you need to measure what is coming in and going out. This is information useful for both you and your doctor.
To measure what is coming out is not easy at all, but if you keep a note of how many times you’re having diarrhea or vomiting that is a good indication of what is going on. It is also important to measure how much fluid you’re taking in. If you use a water bottle or cup that contains a set amount of fluid you can track how many times you drink it dry.
Eat food with a high water content
The liquid in solid food counts toward your daily total. So you can eat healthily and stay hydrated at the same time. Some fruits and vegetables are more than 90% water. Try watermelon, celery, cucumbers, grapefruit and tomatoes which are all 90 percent water
Final thoughts
With cancer treatment side effects causing vomiting or diarrhea it can become relatively easy for cancer patients to become dehydrated quite quickly. By using some simple solutions such as keeping a glass of water by the bed, drinking fluids and sucking on ice chips throughout the day, together with monitoring fluid loss and intake, its possible to avoid dehydration.
We hope that the above tips help and welcome your views, experiences, and any other advice on the subject.
With over 30 years of experience in medical research, business, and patient advocacy, Shara combines her scientific expertise with deep empathy to create thoughtful care packages and educational resources that address the emotional and physical challenges of cancer.
Before founding Cancer Care Parcel, Shara built a distinguished career as a biomedical scientist and entrepreneur, publishing extensively and leading successful ventures in life sciences communication and community engagement. Recognised with the British Empire Medal (BEM) for her services to cancer patients and women in STEM, she continues to champion awareness, dignity, and compassion in cancer care—ensuring that no one feels forgotten during or after treatment.
We strongly advise you to talk with a health care professional about specific medical conditions and treatments.
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