February 26, 2020

4 Things You Should Know About Cancer and Dehydration

Why keeping your fluid consumption high is important

Cancer patient on balcony drinking tea

If you’re undergoing cancer treatment, one issue you need to keep at the forefront of your mind is dehydration. Dehydration is an excessive loss of body fluids and occurs when your body’s fluid output exceeds its fluid intake.


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When you’re undergoing cancer treatment, side effects like vomiting or diarrhea can lead to dehydration. Infections, high fever, bleeding or merely not drinking enough fluids also can lead to dehydration.

Dehydration is a serious condition and can be life-threatening if left untreated. The danger of dehydration is greatest if you live alone, because you may not recognize its signs and effects.

Here are four things cancer care nurse Josette Snyder, BSN, MSN, AOCN, says cancer patients should know about dehydration:


1. Am I dehydrated? Here’s a quick test

You’re dehydrated if you lightly pinch and pull up your skin and it stays standing up in a tent, Snyder says. Other symptoms include:

  • Dry mouth.
  • Loose and crinkled skin.
  • Thick, dry body secretions.
  • Little or no urine output.
  • Dark urine.
  • Headache.
  • Dizziness.

2. Keep track of your fluid intake and output

It’s not easy to tell how much fluid you’re losing unless you measure it. “Rather than measuring the amount of your output, keep track of how many times you’re having diarrhea or vomiting,” Snyder says. “This information will be very helpful when talking to the doctor about dehydration symptoms. It is also important to measure how much fluid you’re taking in. Use a water bottle or cup that contains a set amount of fluid and track how many times you drink it dry.”

3. If you can’t keep fluids down, try ice or little sips of liquids

Sucking on small pieces of ice works can help improve your fluid intake. The downside is that it takes a lot of ice to make an impact. “You also may find that taking small, frequent sips is easier than drinking large amounts at a time,” Snyder says. “Try water, soda, bouillon, juice, or whatever you can tolerate. Avoid alcohol and caffeine because they may increase the effects of dehydration.”


4. Stem the fluid loss when the first signs of dehydration appear

The first step is to manage symptoms that are contributing to dehydration, Snyder says. You should talk with your doctor or nurse for advice about managing these symptoms. The second step is to continue drinking fluids to replace those you’ve lost.

When is it time to call a doctor?

Snyder strongly encourages you to talk with your healthcare professional about your specific medical condition and treatments. But in general, it’s time to call the doctor’s office if you experience:

  • Difficulty keeping fluids down.
  • Uncontrolled symptoms.
  • Fever greater than 100.4o F.
  • Excessive sleepiness.
  • Signs of confusion.

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