10 Signs of Dehydration & How to Prevent Them

• May 2, 2025
• Written by :  Rebecca LaMarca, MSN, APN-BC, CNS

Dehydration happens when the body loses more fluids than it takes in, and a variety of things can cause it. Knowing the signs and symptoms of dehydration can help you catch it early and avoid long-term health consequences. Here are 10 signs of dehydration to be aware of and common causes and ways to prevent it. 

1. Dry Mouth and Throat

When the body doesn’t get enough fluids, it can’t produce normal amounts of saliva. As a result, the first sign of dehydration is usually a dry mouth and throat accompanied by an intense feeling of thirst. 

Other medications and health conditions can cause dry mouth, so many people ignore this symptom. However, if you don’t drink water, it can quickly progress to more intense dehydration. 

The best way to avoid dry mouth is to drink water frequently. Carrying a water bottle with you throughout the day can make it easier to stay hydrated. Sugarless gum and hard candy can also help stimulate saliva production if you’re experiencing dry mouth. 

2. Dark Yellow Urine or Decreased Urination

If you’re wondering how to know if you are dehydrated, pay attention to your urine. When you’re not consuming enough fluids, you won’t produce as much urine as usual. This happens because your kidneys are working to retain as much water as possible. 

When you urinate, you might notice that your urine is dark yellow rather than clear or light yellow. Because your urine is more concentrated, you might also notice a stronger smell. 

If you’re noticing this dehydration symptom, drink plenty of water and avoid drinks that could further affect your urinary system, such as coffee or alcohol. 

3. Fatigue or Low Energy Levels

One of the key signs you’re dehydrated is a feeling of intense fatigue or low energy levels. As dehydration progresses, you may feel unable to stand up or walk. 

Dehydration often happens when exercising or spending time outside in hot weather, so you may not initially notice that you’re more fatigued than usual. However, if you don’t replenish fluids, your blood pressure will continue to drop, making the exhaustion even more intense. 

4. Dry Skin or Lack of Elasticity

If you’re consistently dehydrated, the outer layers of your skin won’t get enough fluids. This can leave your skin feeling dry, itchy, and tight. Your skin might also flake or wrinkle more easily than normal. 

Dehydration affects both the skin on your face and your body. Moisturizing lotions and serums may temporarily relieve these symptoms, but they will quickly return if you are not drinking enough water.  

5. Dizziness or Lightheadedness

When you’re dehydrated, your body doesn’t have enough fluids to circulate blood effectively. This can result in insufficient circulation to the brain, causing a sensation of dizziness and lightheadedness. 

In addition to drinking water, it’s important to sit or lie down immediately if you experience this symptom. This will help prevent you from falling and injuring yourself if you faint. Avoid sudden movements, close your eyes, and relax to let your body recover.  

6. Headache

The lack of circulation brought on by dehydration can also cause intense headaches. This is one of the top 10 signs of dehydration in adults and children and can be acutely intense, even in mild cases of dehydration. The pain can be concentrated anywhere on the head and can feel like a tension headache or an intense migraine. 

Dehydration can also lead to losing key electrolytes, making the headache even more painful. The pain may also get more severe if you move around too quickly. Consuming sports drinks that contain electrolytes can help restore this balance and prevent the headache from worsening. 

7. Rapid Heartbeat or Breathing

Since dehydration interferes with circulation, you might notice your heart beating faster than normal. With less fluid in your body, your circulatory system must work harder to move blood around to reach your extremities. 

Additionally, your body will need to work harder to take in enough oxygen. This can cause you to breathe faster or leave you gasping for air. 

If you notice your breathing or heartbeat speeding up, stop physical activity and sit or lie down if you can. Focus on your breath to regulate your nervous system, and, of course, drink water. 

8. Muscle Cramps or Weakness

When you’re dehydrated, your muscle fibers don’t get the fluids they need to work correctly. As a result, you might experience intense muscle cramping that doesn’t improve with a deep stretch. Your muscles might also feel much weaker than normal, making standing, walking around, or lifting small items difficult. 

If you’re experiencing muscle cramps due to dehydration, it’s important to consume fluids containing electrolytes. This can help restore balance to your muscles to prevent further cramping. 

9. Confusion or Irritability

As dehydration progresses, you might feel abnormally irritable or disoriented. When your body struggles to pump enough blood to the brain, regulating your emotions becomes more difficult, so things that normally would not bother you could upset you. In severe cases, you might feel confused about your surroundings or struggle to complete normal day-to-day activities. 

10. Sunken Eyes or Dry, Sticky Eyes

Dehydration can cause your eyes to feel abnormally dry, itchy, or sticky. The skin around the eyes might also appear sunken as it loses volume and elasticity. If this happens to you, eye drops can help relieve discomfort while your body rehydrates.

Common Causes of Dehydration

There are a variety of possible causes of dehydration to be aware of. These include: 

• Fever: When you have a fever, your body sweats more to stay cool. This causes your body to lose fluids faster than normal. Your metabolism will also speed up, causing your body to consume fluids at a faster rate. 
• Other illnesses: Many illnesses cause vomiting and diarrhea, both of which can result in rapid fluid loss and dehydration. 
• Sweating: During intense physical activity, you’re likely to sweat more than normal. If you don’t take immediate steps to replace these fluids, you could become dehydrated. 
• Hot weather: If you’re outside in high temperatures for an extended period of time, your body will use all available fluids to cool itself down. As a result, dehydration symptoms can set in fast. 
• High altitude: Visiting high-altitude areas may lead to dehydration if you’re not acclimated to the thin air. Less oxygen causes your body to work harder and use up its fluid stores faster, which can dehydrate you. 
• Alcohol: Drinking large amounts of alcohol can quickly cause dehydration. Alcohol is a natural diuretic, so it will cause you to urinate more often and lose fluid at an alarming rate. Extreme alcohol consumption can also lead to vomiting, which creates even more fluid loss. Getting a hangover IV drip can help you replenish these fluids to avoid further complications. 

Awareness of these causes can help you take preventative steps to avoid them. Keep in mind that dehydration can onset rapidly in these scenarios. 

Tips to Prevent Early Signs and Symptoms of Dehydration

It’s important to be proactive in preventing dehydration, especially if you’re exercising or spending time in hot weather. Here are some steps you can take to avoid dehydration: 

• Drink enough fluids: Drink plenty of water. You can also supplement your water with sports drinks that contain plenty of electrolytes. 
• Avoid high amounts of alcohol: Alcohol is a diuretic, so it’s best to keep drinking to a minimum. If you do have a drink of alcohol, follow it up with a glass of water to stay hydrated. 
• Monitor urine color: If your urine is dark yellow or has a strong odor, it’s a sign that it’s time to drink more water. 
• Eat hydrating foods: Incorporate foods that contain a lot of water, such as fruits and vegetables. 
• Limit sugar intake: Like alcohol, sugar is a natural diuretic. Keeping your sugar intake in check can help you avoid dehydration. 

Knowledge is the first step to prevention. Maintaining this level of awareness will help you prevent more severe dehydration symptoms that could require hospitalization. 

Book Your IV Therapy with IV Elements

So, how can you tell if you’re dehydrated? Look for symptoms like fatigue, dry mouth, muscle cramps, and headaches. If you experience these symptoms, take action right away to prevent serious health consequences. 

At IV Elements, we offer Vitamin IV therapy to help you rehydrate quickly. Our IV drips contain the fluids and nutrients your body needs to heal after periods of intense dehydration. Contact us to learn more, or book your session today to get started!

REFERENCES

• Mayo Clinic. Can dehydration lead to serious complications? https://newsnetwork.mayoclinic.org/discussion/dehydration-can-lead-to-serious-complications/ 
• National Library of Medicine. A pilot clinical evaluation of oral mucosal dryness in dehydrated patients using a moisture‐checking device. https://pmc.ncbi.nlm.nih.gov/articles/PMC6483039/ 
• National Library of Medicine. The Effect of Hydration on Urine Color Objectively Evaluated in CIE L*a*b* Color Space. https://pmc.ncbi.nlm.nih.gov/articles/PMC7649145/ 
• News Medical. Levels of Hydration and Cognitive Function. https://www.news-medical.net/health/Levels-of-Hydration-and-Cognitive-Function.aspx 
• National Library of Medicine. Does dietary fluid intake affect skin hydration in healthy humans? A systematic literature review. https://pubmed.ncbi.nlm.nih.gov/29392767/ 
• National Library of Medicine. Hydration Status and Cardiovascular Function. https://pmc.ncbi.nlm.nih.gov/articles/PMC6723555/ 
• National Library of Medicine. Dehydration and Headache. https://pmc.ncbi.nlm.nih.gov/articles/PMC8280611/ 
• National Library of Medicine. Influence of Fluid Ingestion on Heart Rate, Cardiac Autonomic Modulation and Blood Pressure in Response to Physical Exercise: A Systematic Review with Meta-Analysis and Meta-Regression. https://pmc.ncbi.nlm.nih.gov/articles/PMC10650885/ 
• National Library of Medicine. Water intake after dehydration makes muscles more susceptible to cramp but electrolytes reverse that effect. https://pmc.ncbi.nlm.nih.gov/articles/PMC6407543/ 
• National Library of Medicine. Effects of Dehydration and Rehydration on Cognitive Performance and Mood among Male College Students in Cangzhou, China: A Self-Controlled Trial. https://pmc.ncbi.nlm.nih.gov/articles/PMC6603652/ 
• Medical News Today. What to know about dehydration and the eyes. https://www.medicalnewstoday.com/articles/can-dehydration-affect-your-eyes 
• Cleveland Clinic. Dehydration. https://my.clevelandclinic.org/health/diseases/9013-dehydration
• WebMD. How Can I Prevent Dehydration? https://www.webmd.com/a-to-z-guides/prevent-dehydration 

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