How Much Water Should You Drink During a Fever?

January 6, 2026 •

4 min read

According to the Cleveland Clinic, dehydration is a common risk associated with fever, which can worsen symptoms and slow down recovery. Staying hydrated is one of the most effective home remedies for managing a fever and ensuring your body can fight off illness efficiently.

Quick Summary

Maintaining proper fluid intake during a fever is essential to counter fluid loss from sweating and support your body's immune response. The optimal amount of hydration varies based on individual factors, so it is vital to balance intake to avoid dehydration and prevent harmful overhydration.

Key Points

Increase Fluid Intake: A fever accelerates fluid loss through sweating, so it is essential to drink more than your normal daily amount to prevent dehydration.
Take Small, Frequent Sips: Instead of drinking a large volume of water at once, consume small amounts frequently, especially if nausea is a concern, to aid absorption and avoid discomfort.
Monitor Urine Color: Use your urine color as a guide. Pale yellow urine indicates good hydration, while dark yellow suggests you need more fluids.
Replenish Electrolytes with Broth or ORS: If experiencing significant fluid loss from vomiting or diarrhea, supplement plain water with clear broths or oral rehydration solutions to replace lost salts.
Listen to Your Body: Pay attention to symptoms like dry mouth, headaches, and fatigue, which are indicators that you need to rehydrate.
Avoid Sugary and Caffeinated Drinks: Sodas and caffeinated beverages can worsen dehydration and should be limited or avoided during illness.

Why Proper Hydration is Crucial During a Fever

When your body's temperature rises due to a fever, it's a sign that your immune system is actively fighting off an infection. This process increases your metabolic rate and causes you to lose fluids more rapidly through sweating. Without adequate fluid replacement, you can quickly become dehydrated, which further stresses your body and can worsen your condition. Dehydration can lead to headaches, dizziness, fatigue, and can even interfere with your body's ability to regulate its temperature, potentially making your fever worse.

The Science of Fluid Loss

Fluid loss during a fever is a multi-faceted process. Firstly, your body uses sweat as a natural cooling mechanism. As the fever elevates your core temperature, sweating increases dramatically, and this moisture loss depletes your body's water stores. Secondly, other symptoms of the underlying illness, such as vomiting or diarrhea, can exacerbate fluid and electrolyte loss. Finally, a decreased appetite or feeling of sickness can lead to a reduced desire to drink, creating a dangerous cycle where less fluid is taken in, while more is lost.

How to Determine Your Fluid Needs

There is no one-size-fits-all answer for how much water you should drink during a fever. General recommendations suggest increasing your normal daily fluid intake to replenish losses. A good rule of thumb is to listen to your body and focus on drinking small, frequent sips throughout the day. It's more effective to hydrate consistently than to try and chug large amounts at once, especially if you feel nauseous. A reliable indicator of your hydration status is the color of your urine; it should be pale yellow. If it is dark yellow or amber, you need to increase your fluid intake.

Monitoring Hydration

Small, Frequent Sips: Don't wait until you are intensely thirsty. Taking small sips of water or other fluids every 15-20 minutes can prevent your stomach from feeling overwhelmed.
Check your urine: Aim for urine that is a pale, lemonade color. Darker urine indicates dehydration, while completely clear urine might suggest you are overhydrating.
Look for other signs: Symptoms like dry mouth, headache, and fatigue can all be indicators that your fluid levels are too low.
Consider Electrolytes: For significant fluid loss due to vomiting or diarrhea, plain water may not be enough. Electrolyte solutions help restore the balance of essential minerals like sodium and potassium.

The Best Fluids for Rehydration

While plain water is always a good choice, other fluids can also be beneficial, especially if you have a sore throat, nausea, or a diminished appetite. For children and adults, a variety of options can help keep you hydrated and comfortable.

A Comparison of Hydrating Fluids


Fluid Type	Benefits	Potential Drawbacks	Recommended For
Plain Water	Replenishes fluids effectively, no added sugar.	Lacks electrolytes; may be unappealing if nauseous.	General rehydration without significant electrolyte loss.
Electrolyte Drinks	Restores crucial electrolytes lost through sweating, vomiting, or diarrhea.	Can be high in sugar; check labels for lower-sugar or sugar-free options.	Rehydration after significant fluid loss.
Clear Broths	Provides fluids, sodium, and nutrients; soothing on a sore throat.	May be high in sodium; not suitable for those on low-salt diets.	Easy-to-digest hydration with some nutrients.
Herbal Tea (Decaffeinated)	Soothing, warm fluid; some herbs like ginger can help with nausea.	Caffeine can be dehydrating; avoid if it irritates your stomach.	Soothing comfort and gentle hydration.
Popsicles/Ice Chips	Easy way to consume fluids if drinking is difficult; can be soothing.	Can contain high levels of sugar, so use in moderation.	Appealing option for children and those with nausea.

What to Avoid

To maximize your recovery, it's best to avoid certain beverages. Caffeinated drinks like coffee and some teas, as well as alcohol, can act as diuretics and cause further fluid loss. Highly sugary drinks and sodas can also be counterproductive, as excessive sugar intake can aggravate diarrhea and offer little nutritional benefit.

The Dangers of Overhydration

While dehydration is a more common concern during a fever, drinking excessive amounts of plain water can also be dangerous. The condition, known as hyponatremia, occurs when the body's sodium levels become diluted due to too much water intake. This can cause cells to swell, including in the brain, leading to serious neurological issues. This risk is generally low for most people but becomes a concern when fluid loss is high (like with persistent vomiting or diarrhea), and only plain water is consumed to replace it. Therefore, for sustained fluid loss, it's advisable to switch to an electrolyte-rich solution to maintain mineral balance. For more detailed information on hyponatremia, you can consult a trusted medical resource like WebMD.

Conclusion

Navigating proper hydration during a fever is a matter of balance and mindful listening to your body's signals. The key is to increase your fluid intake beyond your normal baseline, focusing on small, regular sips of water, broths, and electrolyte solutions. Be vigilant for signs of dehydration, such as dark urine, and choose hydrating fluids wisely. While a fever can deplete your fluid reserves, an informed approach to rehydration will support your immune system and help you recover as comfortably and quickly as possible.

Frequently Asked Questions

While there is no fixed amount, 'plenty' means increasing your normal fluid intake. A good approach is to drink small, frequent sips throughout the day and use pale yellow urine as an indicator of adequate hydration.

Diluted fruit juice is acceptable, but full-strength juice can contain high sugar levels that may aggravate diarrhea. Other options like popsicles or electrolyte solutions are often better tolerated by children.

Yes, excessive intake of plain water, especially when also losing electrolytes, can lead to a dangerous condition called hyponatremia. The key is balance and using electrolyte-rich fluids when necessary.

Key signs of dehydration include dark urine, a dry mouth, lips, and tongue, fatigue, dizziness, and a rapid heartbeat. In infants, look for fewer wet diapers and a sunken fontanelle.

Sports drinks can help replenish electrolytes lost through sweating, vomiting, or diarrhea. However, many are high in sugar. Oral rehydration solutions (ORS) are often a better choice as they have a more balanced ratio of sugar and electrolytes.

The temperature of the water is less important than the act of drinking it. Lukewarm or room-temperature water is often well-tolerated. Hot or cold fluids may have a soothing effect, depending on individual preference and symptoms.

Drinking water helps your body regulate its temperature and prevents dehydration, which can worsen a fever. While it supports your body's natural cooling processes, it is not a cure and is best used alongside other fever management techniques like rest and medication.