When your child has both a fever and vomiting, the immediate priorities are preventing dehydration, bringing the fever down safely, and knowing which warning signs mean it’s time for medical help. Most cases resolve within 24 to 48 hours with careful home management, but the combination of these two symptoms demands close attention because vomiting makes it harder to keep fluids and medication down.
What Counts as a Fever
A child has a fever at a rectal, ear, or forehead temperature of 100.4°F (38°C) or higher. For an oral reading, the threshold is 100°F (37.8°C), and for an armpit measurement it’s 99°F (37.2°C). These distinctions matter because the method you use changes the number you see. Rectal readings are the most accurate for babies and toddlers.
Any infant under 3 months with a rectal temperature of 100.4°F or higher needs immediate medical evaluation, regardless of how well they seem. At that age the immune system is still developing, and fever can signal serious infection.
Fluids First: Preventing Dehydration
Dehydration is the biggest risk when a child is both feverish and vomiting. Fever increases fluid loss through sweat, and vomiting prevents your child from replacing what’s lost. The goal isn’t to get large volumes down at once. It’s to deliver tiny, steady amounts that the stomach can absorb before triggering another episode.
Start with 5 milliliters (about a teaspoon) of fluid every minute, delivered by spoon or oral syringe. This slow pace sounds tedious, but it works. A child who would vomit after drinking half a cup can often keep down the same volume when it trickles in a teaspoon at a time. Use an oral rehydration solution (available at any pharmacy) rather than juice, soda, or plain water, because it replaces both the fluid and the electrolytes your child is losing.
For mild dehydration, aim for roughly 50 mL per kilogram of your child’s weight over 2 to 4 hours. If dehydration is more noticeable (dry lips, fewer wet diapers, no tears when crying), increase that target to 100 mL per kilogram over the same window. After each vomiting episode, offer an extra 2 mL per kilogram to replace what was just lost. For a 22-pound (10 kg) toddler, that’s about 20 mL, or 4 teaspoons, after each round of vomiting.
Signs of Dehydration to Watch For
- Fewer wet diapers than usual, or in older children, noticeably less urination
- Few or no tears when crying
- Drowsiness or unusual irritability beyond what you’d expect from feeling unwell
- Dry mouth and lips
Bringing the Fever Down
Acetaminophen is the standard fever reducer for children 8 weeks and older. It can be given every 4 to 6 hours as needed, up to 5 times in 24 hours. Ibuprofen is an option for children 6 months and older, given every 6 to 8 hours, up to 4 times in a day. Always dose by your child’s weight, not age. The weight-based dosing information is on the product packaging.
When a child is actively vomiting, keeping oral medication down is the obvious challenge. If your child vomits within minutes of swallowing a dose, it likely didn’t absorb. Acetaminophen suppositories, inserted rectally, bypass the stomach entirely and are a reliable alternative. They’re sold over the counter in pediatric strengths. Make sure you’re buying the children’s version, not the adult product. To insert one, lay your child on their side with the top knee drawn toward the chest, gently push the suppository about half an inch to one inch into the rectum, and hold it in place for a few moments. Have your child stay lying down for about 5 minutes afterward.
Give ibuprofen with a small amount of food or milk if your child can tolerate it, since it can irritate an empty stomach. In the middle of a vomiting illness, acetaminophen (oral or rectal) is often the easier choice for that reason.
Room and Clothing Adjustments
Keep the room around 64°F (18°C) with fresh air circulating. Dress your child in light layers rather than bundling them up. If they’re shivering, add a thin blanket; if they’re sweating heavily, remove a layer. The instinct to pile on blankets when a child has chills can actually trap heat and push the fever higher. Avoid ice baths or cold sponging, which cause shivering and can make your child more uncomfortable without meaningfully lowering their core temperature.
When and What to Feed
You don’t need to restrict your child to the old BRAT diet (bananas, rice, applesauce, toast). The American Academy of Pediatrics considers it too limited and no longer recommends it. Once vomiting slows down and your child shows interest in food, offer their normal diet. Studies consistently show that returning to a regular, age-appropriate diet shortens the duration of illness compared to restrictive eating.
That said, start small. A few bites of familiar food are better than a full plate that overwhelms a sensitive stomach. Avoid greasy, spicy, or very sugary foods in the first day or two, not because they’re medically harmful, but because they’re more likely to trigger nausea. If your child doesn’t want to eat for the first 12 to 24 hours, that’s fine as long as they’re taking in fluids.
When Vomiting Won’t Stop
If your child cannot keep any fluids down for several hours despite the slow-sip method, they may need medical intervention. Doctors sometimes prescribe an anti-nausea medication to break the cycle of vomiting and allow oral rehydration to succeed. This medication dissolves on the tongue, so it doesn’t need to be swallowed with water, making it practical even during active vomiting. It’s generally used for children 4 and older and is a short-term solution to prevent a trip to the emergency room for IV fluids.
Warning Signs That Need Immediate Attention
Most fever-and-vomiting episodes in children are caused by common viral infections and resolve on their own. But certain signs indicate something more serious is happening:
- Green or yellow-green vomit (bile-colored), which can signal a bowel obstruction
- Blood in the vomit or vomit that looks like coffee grounds
- A stiff neck combined with fever, which raises concern for meningitis
- Extreme sleepiness or difficulty waking your child
- A bulging soft spot on an infant’s head
- No wet diapers for 6 or more hours in an infant, or no urination for 8 or more hours in an older child
- Fever lasting more than 3 days, or fever above 104°F (40°C) that doesn’t respond to medication
- A rash that doesn’t fade when you press a glass against it
A child who has had a head injury recently and then begins vomiting several times with changes in alertness also needs emergency evaluation, as vomiting after head trauma can indicate a concussion or something more serious.