Children are more vulnerable to dehydration than adults, and in pediatric care, even mild fluid loss needs attention. Parents often ask: Can dehydration cause a fever in kids? To answer this, it’s important to understand how water supports your child’s body.
Water makes up about 50–70% of the body and plays a key role in:
- Regulating temperature
- Flushing out toxins
- Protecting joints and tissues
- Supporting vital organs
When kids don’t get enough water intake, they can become dehydrated, sometimes losing essential electrolytes like sodium and potassium. Mild dehydration may be managed at home, but if ignored, it can quickly turn severe, especially in children.
What Can Cause Dehydration in Kids?
Your child’s body can lose water in different ways, and some causes are more common in children:
Vomiting and diarrhea: Frequent water loss from illness is the top cause of dehydration. When children vomit, they lose not only water but also essential electrolytes needed for normal body functions. Diarrhea can worsen this loss rapidly, especially in young children who have smaller liquid reserves.
Heat and activity: Playing outdoors in hot weather without enough water can lead to dehydration and even heat-related illnesses. Children sweat more during physical activity, and if they don’t replace those fluids, they can overheat quickly. This is especially dangerous in summer when kids may not recognize thirst until dehydration has already set in.
Illnesses that affect drinking: Children may avoid drinking if they have a sore throat, mouth pain, or other conditions that make swallowing uncomfortable. Illness can also lower their appetite and thirst, making it harder for them to stay hydrated. Even mild illnesses can become risky if kids refuse fluids for an extended period.
Feeding issues in babies: Infants can quickly become dehydrated if they struggle with breastfeeding or bottle feeding. Their small bodies require frequent feeding, and missing even a few feedings may cause fluid imbalance. Parents should pay close attention to wet diaper counts, as they’re an important sign of hydration in babies.
Understanding these causes helps parents act quickly to replace lost liquid and prevent complications.
Signs of Dehydration in Kids
Signs of dehydration can vary depending on the severity. Besides being thirsty, parents may notice different changes in their child:
Mild or Moderate Dehydration
- Dry mouth and lips
- Few or no tears when crying
- Fewer bathroom trips or fewer wet diapers
- Sunken eyes
- In infants: sunken soft spot on the head
- Crankiness or irritability
Severe Dehydration
- Extreme tiredness or lethargy
- Rapid or labored breathing
- No tears when crying
- Dizziness or difficulty standing
- No urination for more than 12 hours
- Fainting or passing out
If severe symptoms appear, it’s an emergency and requires immediate medical care.
How to Manage Dehydration When Your Child Has a Fever
Fever is a common cause of dehydration in kids. A fever is the body’s natural response to infection or illness, but it also increases water loss. Here’s why:
- A sudden rise in body temperature uses up more fluids.
- Fever often reduces appetite and thirst, making it harder for children to drink.
- Kids may struggle to keep fluids down if they are vomiting or not feeling well.
How parents can help:
- Encourage frequent small sips of water or oral rehydration solution (ORS).
- Offer electrolyte-rich fluids if recommended by a doctor.
- Keep your child cool and resting to reduce fluid loss.
- Avoid sugary drinks or sodas that can worsen dehydration.
Risk Factors for Dehydration
Anyone can get dehydrated, but some groups are more vulnerable than others:
- Infants and children: This group is at the highest risk. They are more likely to experience severe diarrhea or vomiting, lose fluids quickly with high fevers or burns, and cannot always express thirst or get water themselves.
- Older adults: Seniors may have a reduced sense of thirst, chronic illnesses, or medications that increase fluid loss.
- People with chronic illnesses: Conditions like diabetes, kidney disease, or heart problems can increase dehydration risk.
- Active individuals in hot weather: Athletes, outdoor workers, or children playing outside in the heat can dehydrate quickly.
While mild cases can often be managed at home, severe dehydration and fever require immediate professional care.
Dehydration Care at Austin Emergency Center
If your child shows signs of dehydration with a high fever, persistent vomiting or diarrhea, unusual drowsiness, or is unable to keep fluids down, it’s time to get emergency help. At Austin Emergency Center, our pediatric team provides quick diagnosis, IV fluids when needed, and expert treatment to help your child recover safely. Recognizing who is at risk helps parents and caregivers act early to prevent complications. In many cases, dehydration can contribute to a rise in body temperature, and fevers can also worsen fluid loss.