Feverish children - management
Exam Tips
- In OSCEs, state that antipyretics are for distress/discomfort, not for treating the number on the thermometer.
- A parent-reported fever counts clinically even if afebrile in clinic; mention diurnal variation and measurement-site variability.
- Say explicitly: no aspirin under 16 years, no simultaneous paracetamol plus ibuprofen, and no routine prophylactic antipyretics for febrile seizures.
- Include safety-net red flags and follow-up timeframe in every discharge plan.
- Image memory aid: review the NICE traffic-light risk table figure for fever in under-5s (green/amber/red) before exams.
Definition
In children aged 1 month to 16 years, fever is a regulated rise in core body temperature, usually due to infection, and is typically defined clinically as 38.0 C or above. In practice, a parent-reported fever should be taken seriously even if the child is afebrile at assessment, because temperature varies by site, technique, and time of day.
Pathophysiology
Exogenous pyrogens (for example viral or bacterial products) trigger innate immune cells to release cytokines such as IL-1, IL-6, and TNF-alpha, which increase hypothalamic prostaglandin E2 and raise the thermoregulatory set-point. The child then generates and conserves heat (shivering, vasoconstriction) until body temperature reaches the new set-point; when the set-point falls, vasodilation and sweating promote heat loss. Fever may inhibit pathogen replication and enhance immune function, but in a minority of children the febrile presentation reflects non-infectious inflammation (for example Kawasaki disease) or malignancy.
Risk Factors
- Young age, especially infants under 3 months
- Incomplete immunization status
- Recent close contact with infectious illness (household or nursery)
- Comorbidity increasing risk of severe infection (for example immunosuppression, chronic cardiorespiratory or renal disease)
- Dehydration or poor oral intake
- Previous febrile seizure (risk of recurrence, not necessarily serious bacterial infection)
Clinical Features
Symptoms
- Fever or history of fever reported by parent/carer
- Irritability, reduced activity, lethargy, or altered behaviour
- Poor feeding, reduced fluid intake, vomiting, or diarrhoea
- Respiratory symptoms (cough, coryza, breathlessness)
- Urinary symptoms (dysuria, frequency, foul-smelling urine)
- Headache, photophobia, neck pain, limb pain, or non-blanching rash
Signs
- Measured temperature 38 C or higher
- Tachycardia and/or tachypnoea for age
- Signs of dehydration (dry mucosa, reduced urine output, delayed capillary refill)
- Mottled/pale/blue skin or poor peripheral perfusion
- Reduced consciousness, weak high-pitched cry, or reduced response to social cues
- Focal signs suggesting source (for example otitis media, tonsillitis, chest findings, abdominal tenderness)
Investigations
Management
Lifestyle Modifications
- Assess and treat the likely source if identified; if no focus and child is otherwise well, avoid unnecessary antibiotics
- Encourage regular fluids and monitor urine output to prevent dehydration
- Use light clothing and avoid over-wrapping; keep child comfortable rather than aggressively cooling
- Give clear safety-net advice: seek urgent review for breathing difficulty, non-blanching rash, seizures, reduced responsiveness, persistent vomiting, poor urine output, or worsening parental concern
- Use a medication diary (drug, dose, time) to reduce dosing errors
- Accept parent-reported fever as clinically meaningful even if temperature is normal in clinic
Pharmacological Treatment
Antipyretic analgesic (paracetamol, oral)
- Months: 30-60 mg every 8 hours as needed (max 60 mg/kg/day; off-label for fever in this age band)
- Months: 60 mg every 4-6 hours if needed (max 4 doses/24 h)
- Months: 120 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 180 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 240 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 240-250 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 360-375 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 480-500 mg every 4-6 hours if needed (max 4 doses/24 h)
- Years: 480-750 mg every 4-6 hours if needed (max 4 doses/24 h)
Use only if the child is distressed/uncomfortable, not solely to normalize temperature. Stop once comfortable. Do not exceed daily maximum or combine with other paracetamol-containing products.
NSAID antipyretic (ibuprofen, oral)
- Months: 50 mg three times daily (max 30 mg/kg/day in 3-4 divided doses)
- Months: 50 mg three to four times daily (max 30 mg/kg/day)
- Years: 100 mg three times daily (max 30 mg/kg/day)
- Years: 150 mg three times daily (max 30 mg/kg/day)
- Years: 200 mg three times daily (max 30 mg/kg/day)
- Years: 300 mg three times daily (max 30 mg/kg/day)
- Years: initially 300-400 mg three to four times daily; may increase if needed (usual UK max constrained by age/weight and product advice)
Use as an alternative to paracetamol based on comorbidity/cautions. Avoid or use great caution in dehydration/hypovolaemia due to AKI risk. Under 3 months or under 5 kg is generally off-label and specialist-led.
Antipyretic strategy and safety
- Start with ONE agent: paracetamol OR ibuprofen
- If ineffective, switch to the other agent
- Do NOT give both simultaneously
- Only consider alternating if distress persists or symptoms recur before next dose is due
Do not use aspirin in under 16s (Reye syndrome risk). Do not give prophylactic antipyretics to prevent febrile seizures. Do not use fever response after 1-2 hours to rule in/out serious illness.
Antibiotics
- No routine oral antibiotic in fever without an apparent bacterial focus
Prescribe only when there is a clear suspected/confirmed bacterial source or high-risk features requiring treatment per local antimicrobial guidance.
Complications
- Dehydration requiring urgent rehydration
- Medication error or accidental overdose (duplicate paracetamol/ibuprofen products)
- Acute kidney injury when NSAIDs are used in dehydrated/hypovolaemic children
- Febrile seizures
- Missed serious bacterial infection, sepsis, or meningitis if red flags are not recognized early
Prognosis
Most febrile illnesses in children are self-limiting viral infections with good recovery using supportive care. Prognosis worsens when serious bacterial infection is present, so early risk stratification, clear safety-netting, and timely escalation are key determinants of outcome.
Sources & References
✅NICE Guidelines(1)
- Feverish children - management[overview]