Pharmacology

Fever

A Comprehensive Article

Infections

Fever is a common symptom of infection or inflammation, characterized by an elevated body temperature (typically >37.5°C axillary or >38°C orally). In Ghana, fever often signals endemic diseases like malaria, typhoid, or tuberculosis, requiring a systematic approach to identify the underlying cause and provide appropriate management.

🌡️ Overview and Pathophysiology

Fever results from the body's immune response to pyrogens, resetting the hypothalamic thermostat:

Causes

  • Infectious: Malaria, typhoid, TB, viral infections
  • Non-Infectious: Autoimmune diseases, malignancy, heat stroke
  • Risk Factors: Endemic exposure, immunosuppression

Mechanisms

  • Pyrogens: Endogenous (IL-1, IL-6) or exogenous (bacterial toxins)
  • Response: Increased heat production, vasoconstriction
  • Key Point: Fever aids immune defense but can lead to complications if severe

🔍 Clinical Presentation

Fever presentation varies with underlying cause:

Symptoms

General: Chills, sweats, fatigue, headache
Specific: Cough (TB), abdominal pain (typhoid), joint pain (malaria)
Children: Irritability, poor feeding

Signs

Vital: Temperature >37.5°C axillary, tachycardia, tachypnea
Systemic: Pallor (anemia), lymphadenopathy, rash
Other: Splenomegaly, hepatomegaly (depending on cause)

Red Flags:
  • Temperature >40°C or persistent >48 hours
  • Altered consciousness, seizures
  • Dehydration, severe weakness, or respiratory distress

🧪 Diagnosis

Identify the cause through targeted investigations:

Investigations

First-Line: Full Blood Count (FBC), malaria RDT/microscopy
Further Tests: Blood culture, Widal test (typhoid), chest X-ray (TB)
Supportive: Urinalysis, stool R/E, inflammatory markers (CRP/ESR)

Clinical Insight: Treat empirically for malaria or typhoid in endemic areas if testing delayed; confirm with labs.

💊 Treatment

Management targets the underlying cause and symptom relief.

Non-Pharmacological

Temperature Control: Tepid sponging, light clothing
Hydration: Oral rehydration salts (ORS) or IV fluids if dehydrated
Rest: Encourage adequate rest and nutrition

Paracetamol

  • Dose: 10-15 mg/kg every 6-8 hours (max 60 mg/kg/day)
  • Route: Oral or rectal
  • Indication: Fever relief

Ibuprofen

  • Dose: 5-10 mg/kg every 6-8 hours (max 40 mg/kg/day)
  • Route: Oral
  • Indication: Fever and pain relief (avoid in dehydration)

Specific Therapy

  • Malaria: Artemether-Lumefantrine or Artesunate-Amodiaquine (see malaria guidelines)
  • Typhoid: Ciprofloxacin 500 mg 12 hourly x 7-10 days
  • TB: Refer to TB treatment protocol
Important Notes:
  • Avoid aspirin in children due to Reye’s syndrome risk
  • Escalate if no improvement after 48 hours or worsening symptoms
  • Monitor for dehydration and electrolyte imbalance

🤰 Special Populations

Adjust management based on age and condition:

Children

Focus: Weight-based dosing, monitor for seizures
Red Flags: Fever >39°C, lethargy, or refusal to feed

Pregnancy

Caution: Use paracetamol; avoid ibuprofen unless benefits outweigh risks
Investigation: Rule out malaria, UTI

Note: Seek obstetric consultation if fever persists.

🚨 Referral Criteria

Immediate Referral:
  • Fever >40°C or persistent >48 hours despite treatment
  • Signs of severe infection (e.g., sepsis, meningitis)
  • Children with seizures or dehydration

Initiate empiric treatment and transfer to higher facility if needed.

🧠 Key Takeaways

  • Assess Cause: Investigate underlying infection (e.g., malaria, typhoid)
  • Symptom Relief: Paracetamol or ibuprofen; tepid sponging
  • Hydrate: Ensure adequate fluid intake
  • Monitor: Watch for red flags, escalate if no improvement
  • Special Care: Adjust for children and pregnant women
  • Refer: For severe or persistent cases