November 13, 2020
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10 Symptoms of Dehydration in the Elderly

Symptoms of dehydration in the elderly to look for include: dry mouth, fatigue, muscle cramps, sunken eyes, reduced urine output, dark urine, low blood pressure, elevated heart rate, confusion and difficulty walking.

medication and medical equipment to reduce symptoms of dehydration in the elderly

The human body is up to 60% water in healthy adults. According to hydration for health, over the course of a normal lifespan, we lose approximately 15% of our body’s water. This can lead to symptoms of dehydration in the elderly and serious complications including: decreased cognitive function, changes in mood, decreased alertness and energy and increased risk of falls, increased constipation, and hospitalizations. 


  • Dry Mouth: Occasional dry mouth is not abnormal and can be related to stress or nervousness. It can also be caused as a side effect of certain medications. But if dry mouth persists and is found in addition to the symptoms listed below, dehydration is likely a cause. 
  • Fatigue: This is caused by a reduction in blood volume that causes the heart to work harder to pump needed nutrients and oxygen throughout your system. Some fatigue is normal with increased work output with age, but constant fatigue may indicate dehydration for seniors.
  • Muscle Cramps: This symptom of dehydration in the elderly is the result of specific muscles not getting enough oxygen and nutrients due to reduced blood supply caused by dehydration. Increased fluid intake and electrolytes should help.
  • Sunken Eyes: The most common cause of this appearance to the eyes and darkened skin around the eyes is dehydration. This decrease in fluid in the tissue thins out the skin allowing blood vessels to become more visible through the skin.
  • Reduced Urine Output: This is caused by reduced fluid in the body. Your body needs all the fluid it has and so your kidneys work to keep as much fluid as possible in your bloodstream. 
  • Dark Urine: This is caused by your kidneys filtering out the waste from your bloodstream while at the same time trying to maintain as much hydration as possible. The result is darker colored urine.
  • Low Blood Pressure: Any blood pressure under 90/60 mm Hg is considered too low and hypotensive. Low blood pressure can result in lightheadedness, dizziness or passing out with quick movement. Check out this article for blood pressure ranges in the elderly. 
  • Elevated Heart Rate: A heart rate over 100 beats per minute is considered tachycardia and can be the result of dehydration. If heart rate remains over 100 beats per minute after consuming a large glass of water, you may need to contact your physician. 
  • Confusion: Decreased cognition and confusion can result from lack of sufficient blood flow to the brain caused by decreased hydration status. If confusion persists, contact the physician. 
  • Difficulty Walking: This can result from reduced blood volumes which will reduce the oxygen, nutrient and waste carrying capacity of the blood. This makes muscle function ineffective and leads to increased risk of fall and serious injury. 
low blood pressure being checked as one of the symptoms of dehydration in the elderly


Dehydration is caused by a negative fluid inflow/outflow balance. This is the result of loss of fluid from urination, bowel movements, sweating, vomiting, or bleeding without adequate water intake to replace this lost fluid. There are many reasons seniors are especially at risk for dehydration including: decreased sense of thirst, medication side effects, reduced mobility, reduced cognition, medical conditions. 

  • Decreased sense of thirst: This is a normal part of aging and requires one to be extra vigilant when it comes to drinking water, even if you don’t feel thirsty.
  • Medication side effects: Decreased fluid retention and dehydration is a side effect of certain medications including diuretics, laxatives and chemotherapy drugs. Depending on the reason the medication was prescribed, increased fluid intake may be necessary. Consult with your physician.
  • Reduced mobility: This is a normal part of aging and makes getting to the restroom or retrieving a glass of water more difficult. Though when combined with increased frequency of urination, people tend to try to limit their fluid intake to reduce “excessive” trips to the restroom. This should be discouraged as the resulting dehydration in the elderly can lead to more negative health outcomes. 
  • Reduced cognition: This increase in forgetfulness makes one less likely to realize they have not had anything to drink in quite some time and along with the decreased sense of thirst will increase risk of dehydration.
  • Medical conditions: Diabetes especially when it is uncontrolled and kidney disease can lead to increased risk of dehydration and should be monitored. 
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When you notice any of the above causes or symptoms of dehydration in the elderly, it is best to encourage fluid intake even when they are not thirsty. Water is the best option for hydration and tea, coffee and alcohol are diuretics which will reduce water retention. Encourage water consumption throughout the day by keeping a water bottle close by and reminding them to drink a bit with each meal, between meals and after any type of activity. Fruits, vegetables and soups can also be good for additional fluid intake at meal times. With increased preparedness and consistency you can help your loved one decrease their risk of complications related to dehydration.

That's all for today.

Take care, keep mom safe and have a great day!


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