What is the appropriate paracetamol (acetaminophen) dosing for a fever of 38 °C in a healthy adult and in children, and what are the contraindications?

Paracetamol Dosing for 38°C Fever

For a body temperature of 38°C, paracetamol is generally not indicated, as most guidelines recommend treating fever only when temperature exceeds 38.5°C in adults, and the primary goal should be improving comfort rather than normalizing temperature. 1, 2

Temperature Threshold for Treatment

• 38°C does not require antipyretic treatment in most clinical contexts, as this temperature is below the commonly accepted threshold for pharmacological intervention 1
• The 2019-nCoV pneumonia guideline specifically states: "When the temperature is higher than 38.5°C, ibuprofen can be used for antipyretic...and the temperature below 38°C is acceptable" 1
• Fever itself is a beneficial physiologic mechanism that aids in fighting infection and does not worsen illness course or cause long-term neurologic complications 2

When Paracetamol IS Appropriate at 38°C

Paracetamol should be given when fever is combined with pain or significant discomfort, not for fever reduction alone 3

Adult Dosing (when indicated):

• 1000 mg (1 gram) per dose is the optimal single dose for maximum antipyretic effect in adults 4
• Can be repeated every 4-6 hours as needed 4
• Maximum daily dose: 4000 mg (4 grams) - never exceed this to avoid hepatotoxicity 4, 5
• Onset of antipyretic effect occurs within hours, with mean temperature reduction of only 0.26°C within 4 hours 4

Pediatric Dosing (when indicated):

• 15 mg/kg every 4 hours as recommended by the Centers for Disease Control and Prevention 4
• Focus on improving overall comfort rather than normalizing temperature 2

Critical Clinical Caveats

Limited Effectiveness

• Paracetamol is modestly effective and patients with temperatures exceeding 38°C may be relatively unresponsive to treatment 4
• The drug shows "no important advantage compared with placebo" in fever control according to some evidence 6
• Does NOT prevent febrile seizures in children despite common misconceptions 4, 2

Contraindications and Warnings

• Avoid in heatstroke due to potential aggravation of coagulopathy and liver injury 7
• Hepatotoxicity risk with doses exceeding 4000 mg daily 4, 3
• May adversely affect immune response by inhibiting beneficial fever 3

Evidence Quality Considerations

The recommendation against treating 38°C fever comes from high-quality guideline evidence 1, while the American Heart Association notes that treating elevated temperature in conditions like intracerebral hemorrhage "may be reasonable" but acknowledges conflicting evidence on whether it improves functional outcomes 1. The European Stroke Organisation similarly states there is "insufficient evidence from RCTs to make strong recommendations" on fever treatment 1.

The most recent and highest quality evidence (2020 guideline) clearly establishes 38.5°C as the treatment threshold, making paracetamol unnecessary at 38°C unless the patient has concurrent pain or significant discomfort 1.