Infant high fever and febrile seizures emergency guide¶

A fever in an infant or toddler is not an illness by itself; it is a physiological immune response engineered by the body to fight off viral or bacterial infections. However, the medical danger of a fever depends heavily on the exact age of the child. While a 2-year-old toddler running a fever of 39.0 degrees Celsius (102.2 degrees Fahrenheit) who is drinking fluids and playing may safely recover at home, a newborn under 3 months (90 days) old with a rectal temperature of just 38.0 degrees Celsius (100.4 degrees Fahrenheit) is a time-critical medical emergency requiring immediate hospital evaluation.

In addition, rapid spikes in body temperature in children between 6 months and 5 years old can trigger a febrile seizure (a convulsion caused by fever). Witnessing your baby or toddler stiffen, shake, or roll their eyes back is terrifying for any parent, but knowing exact age-based temperature rules and seizure first aid allows you to keep your child safe and get emergency care without delay.

Do this now¶

1. If your child is currently having a seizure, place them on their side on a flat, safe surface. Lay the child gently on the floor or a firm bed away from hard furniture or stairs, roll them onto their side (the recovery position) so saliva or vomit can drain from their mouth, and start timing the seizure on your phone.
2. Never put anything inside a seizing child's mouth and never put them in a bath. Do not try to hold their tongue down with your fingers or a spoon, do not try to restrain their shaking limbs, and do not place them in cold water.
3. Call emergency services immediately if the seizure lasts more than 5 minutes or breathing is impaired. Call your local emergency number (911 in the United States and Canada, 112 across the European Union, 999 in the United Kingdom) or check emergency numbers if the convulsion passes the 5-minute mark, if the child turns blue around the lips, or if they have trouble breathing afterward.
4. Go straight to the emergency room if a baby under 3 months (90 days) old has a rectal temperature of 38.0 °C (100.4 °F) or higher. Do not wait until morning for a pediatrician's office to open, and do not give fever-reducing medicine before the emergency doctor examines the newborn.
5. Perform the "glass test" if you see any rash alongside a fever. Press the side of a clear drinking glass firmly against the skin rash. If the red or purple spots do not fade (blanch) under the pressure of the glass, call 911, 112, or 999 immediately for suspected meningitis or sepsis.

flowchart TD
    A["Child feels hot, lethargic, or has a seizure"] --> B{"Is the child currently having a seizure?"}
    B -->|"Yes"| C["Roll child onto side on safe floor and time the seizure"]
    C --> D{"Lasts over 5 minutes or breathing trouble?"}
    D -->|"Yes"| E["Call 911, 112, or 999 immediately"]
    D -->|"No: Stops under 5 minutes"| F["Seek urgent medical evaluation to check fever source"]
    B -->|"No"| G["Take accurate temperature: Rectal for babies under 3 years"]
    G --> H{"How old is the child?"}
    H -->|"Under 3 months: 38.0 C / 100.4 F or higher"| I["Go to Emergency Room immediately; give NO medicine first"]
    H -->|"3 to 6 months: 38.0 C / 100.4 F or higher"| J["Contact doctor today; go to ER if ≥ 38.9 C / 102.0 F or lethargic"]
    H -->|"Over 6 months"| K["Assess behavior, hydration, breathing, and red flag symptoms"]

Critical age-by-age fever rules¶

According to the American Academy of Pediatrics (AAP), the UK National Institute for Health and Care Excellence (NICE), and the World Health Organization (WHO), a true clinical fever in an infant is defined as a core (rectal) temperature of 38.0 degrees Celsius (100.4 degrees Fahrenheit) or higher. Because a newborn's immune system and blood-brain barrier are still immature, a minor fever in the first weeks of life can be the sole early sign of a life-threatening bacterial infection.

Use this age-stratified triage table to determine your immediate next step:

Red-flag symptoms requiring an immediate ambulance or ER trip¶

Regardless of the exact number on the thermometer or the child's age, the way your child acts, breathes, and looks is more important than the temperature reading alone. Call 911, 112, or 999 or go straight to the nearest emergency department if a fever is accompanied by any of these danger signs:

• Non-blanching purple or dark red rash (The Glass Test): Small pinpoint red spots (petechiae) or purple bruise-like patches (purpura) that do not fade when you press the side of a clear glass firmly against the skin are a classic warning sign of meningococcal septicemia or meningitis.
• Extreme lethargy, floppiness, or difficulty waking: The baby or child is limp like a ragdoll, does not make eye contact, fails to cry during examination, or cannot be woken up to feed.
• High-pitched, weak, or continuous inconsolable crying: A high-pitched, abnormal whimper or screech in an infant, or a baby who cries worse when picked up or when their neck is gently moved.
• Stiff neck or bulging/sunken fontanelle: A stiff neck in an older baby or toddler, a tense bulging soft spot (fontanelle) on the top of an infant's head when sitting upright (indicating pressure around the brain), or a deeply sunken soft spot (indicating severe dehydration).
• Respiratory distress: Fast, labored breathing; nostrils flaring with every breath; skin pulling in tightly around the ribs, breastbone, or collarbones (retractions); or a grunting sound at the end of each breath.
• Blue, gray, pale, or mottled skin: Bluish or gray discoloration around the lips, tongue, or fingernails, or blotchy, lacy-looking pale skin with cold hands and feet (a sign of sepsis and septic shock).
• Severe dehydration: No wet diapers for 8 to 12 hours in an infant, crying without visible tears, a bone-dry mouth and tongue, or persistent green (bilious) vomiting.

How to take an accurate infant temperature¶

Many parents rely on forehead strips, pacifier thermometers, or wrist scanners that give dangerously inaccurate readings during an emergency. When deciding whether a newborn needs to go to the emergency room at 2:00 AM, you need an exact core temperature.

Rectal temperature (The gold standard for babies under 3 years)¶

Pediatric emergency physicians rely on a digital rectal thermometer for infants and toddlers under 3 years old because ear, forehead, and armpit readings can miss a neonatal fever or give a false alarm.

1. Use a clean digital thermometer with a flexible tip (never use an old glass mercury thermometer, which can break and cause chemical poisoning).
2. Wash the tip with soap and lukewarm water or rubbing alcohol, rinse it cool, and coat the silver tip with a small dab of water-soluble lubricant or petroleum jelly (Vaseline).
3. Place your baby tummy-down across your lap or on their back on a changing table with their knees bent up toward their chest.
4. Gently insert the lubricated silver tip only 1.25 to 2.5 centimeters (0.5 to 1 inch) into the rectum, stopping immediately if you feel any resistance. Hold the thermometer steady between your fingers while cupping the baby's bottom so they do not wiggle.
5. Wait until the thermometer beeps, remove it, and read the exact digital number. A rectal reading of 38.0 °C (100.4 °F) or higher is a true fever.

Alternative thermometer methods by age¶

• Temporal artery (forehead) infrared scanners: Useful for infants over 3 months old when used properly across the forehead sweep, though sweating or a cold room can skew results. Always confirm borderline readings in young infants with a rectal check.
• Axillary (armpit) digital thermometer: Can be used as an initial screening tool by placing the digital tip high in a dry armpit and holding the baby's arm snugly against their chest until it beeps. Axillary temperatures run roughly 0.5 °C (1.0 °F) lower than core rectal temperature; if an infant's armpit reading is 37.4 °C (99.3 °F) or higher, recheck rectally.
• Tympanic (ear) thermometer: Only accurate for children over 6 months old. Under 6 months, an infant's ear canal is too narrow and curved for the infrared sensor to read the eardrum accurately.

Step-by-step response to a febrile seizure¶

Approximately 2 to 5 percent of all children between the ages of 6 months and 5 years (most commonly between 12 and 18 months) will experience at least one febrile seizure. Febrile seizures are triggered by the speed at which a child's core temperature rises, often occurring during the very first hours of a viral infection (such as roseola, influenza, or an ear infection), sometimes before parents even realize the child had a fever.

During a simple febrile seizure, a child typically loses consciousness, rolls their eyes back, stiffens their arms and legs, and jerks rhythmically on both sides of the body for 1 to 3 minutes, followed by a brief period of deep sleepiness (the postictal phase). While terrifying to watch, simple febrile seizures do not cause brain damage, intellectual disability, or epilepsy.

Immediate first aid during the convulsion¶

1. Stay calm and check the clock. Note the exact minute and second the seizure started. Doctors need to know the exact duration, and 60 seconds can feel like 10 minutes when you are panicked.
2. Place the child on the floor on their side. Gently move the child away from hard edges, toys, or furniture and roll them onto their side (the recovery position). This keeps their tongue from falling back into their airway and allows drool or vomit to drain safely out of the mouth.
3. Loosen tight clothing around the neck. Unbutton collars or unzip sleep sacks, and remove eyeglasses if the child wears them.
4. Do not restrain the shaking and never put anything in their mouth. A seizing child cannot swallow their tongue. Forcing fingers, pacifiers, or spoons between clenched jaws breaks teeth, cuts gums, or causes airway obstruction.
5. Wait until the child is completely awake before giving anything by mouth. Never try to pour liquid acetaminophen, ibuprofen, or water into the mouth of a seizing or drowsy postictal child, as it will go directly into their lungs (aspiration).

   SAFE FEBRILE SEIZURE POSITION (RECOVERY POSITION)
   +-------------------------------------------------------+
   |  1. Lay child on a flat, cushioned floor surface      |
   |  2. Roll child completely onto their LEFT or RIGHT    |
   |     side so saliva/vomit drains out of the mouth      |
   |  3. Tilt head slightly back to keep airway open       |
   |  4. Keep hands and objects OUT of the child's mouth   |
   +-------------------------------------------------------+

Simple versus complex febrile seizures (When to call 911 / 112 / 999)¶

Call your local emergency number immediately if the seizure shows any features of a complex febrile seizure or status epilepticus:

• The seizure lasts longer than 5 minutes.
• Only one side of the body twitches or jerks (focal seizure), such as just the right arm and leg.
• The child has a second seizure within the same 24-hour period.
• The child's breathing stops or does not return to normal once the shaking ends, or their lips and face stay blue (if the child is unresponsive and not breathing normally after the seizure stops, begin pediatric and infant CPR immediately).
• The child remains confused, unresponsive, or unable to move an arm or leg more than 30 to 60 minutes after the seizure ends.
• Even if a first-time febrile seizure stops within 1 to 2 minutes and your child wakes up crying, always have a physician evaluate them promptly to verify that the fever is caused by a standard virus rather than meningitis.

Dangerous fever myths to avoid¶

Well-meaning relatives often pass down traditional home remedies for bringing down a high fever rapidly. Several of these practices are medically dangerous for infants and toddlers:

Safe ways to keep a feverish child comfortable (over 6 months old)¶

Remember that fever reducers like acetaminophen (paracetamol) and ibuprofen do not prevent febrile seizures and do not cure the underlying viral infection; their purpose is simply to relieve body aches so your child can drink fluids and sleep.

• Prioritize hydration above all else: Fever increases fluid loss through sweating and rapid breathing. Offer frequent small sips of breast milk, infant formula (for babies under 1 year), or pediatric oral electrolyte solution (such as Pedialyte or Dioralyte) for toddlers.
• Dress in a single light layer: Do not bundle a feverish baby in heavy blankets or fleece pajamas to "sweat out the fever." Over-bundling traps body heat and can push a moderate fever above 40.0 °C (104.0 °F). Use a single lightweight cotton layer and a light sheet.
• Dose medication strictly by weight, not age: Only for infants over 3 to 6 months old (after checking age rules above), use the oral dosing syringe packaged with the medication and dose strictly according to your child's current weight in kilograms (or pounds). Never use household kitchen teaspoons, and write down the exact time and dose given so two caregivers do not accidentally double-dose the child.

Frequently asked questions¶

Does teething cause a high fever in babies?¶

No, clinical studies show that teething only causes a very slight rise in body temperature (typically below 37.8 degrees Celsius or 100.0 degrees Fahrenheit) and never causes a true clinical fever of 38.0 degrees Celsius (100.4 degrees Fahrenheit) or higher. Attributing a high infant temperature to teething can dangerously delay treatment for an ear infection, urinary tract infection, or viral illness.

Should I alternate acetaminophen and ibuprofen every few hours to keep a fever down?¶

The American Academy of Pediatrics and the UK NICE guidelines advise against routinely alternating or combining acetaminophen (paracetamol) and ibuprofen unless specifically instructed by your pediatrician with a written schedule. Alternating medications significantly increases the risk of accidental overdose calculations at night without providing meaningful clinical benefit over using a single medicine for comfort.

Can a high fever "cook" my toddler's brain or cause brain damage?¶

A natural fever triggered by a viral or bacterial infection is regulated by the brain's hypothalamus thermostat and almost never rises high enough to cause brain damage on its own. Brain injury from body heat typically occurs only during environmental hyperthermia (such as heatstroke from being left in a hot vehicle) when core temperatures exceed 41.5 to 42.0 degrees Celsius (106.7 to 107.6 degrees Fahrenheit).

Why can't I give fever medicine to a baby under 3 months old before going to the hospital?¶

In a newborn under 90 days old, a fever of 38.0 degrees Celsius (100.4 degrees Fahrenheit) may be the only indicator of early bacterial sepsis, meningitis, or pneumonia. Giving acetaminophen before arriving at the emergency department masks the fever, which can obscure the clinical picture during triage and delay life-saving antibiotic therapy.

Related guides¶

• Pediatric and infant CPR and choking
• Seizures and convulsions first aid
• Sepsis and septic shock emergency response
• Child ingested a foreign object, magnet, or button battery
• Global emergency numbers