What is the recommended dosage of paracetamol (acetaminophen) for pain and fever relief?

Paracetamol Dosing for Pain and Fever Relief

For adults with pain or fever, the recommended dose is 500-1000 mg every 4-6 hours, with a maximum single dose of 1000 mg and a maximum daily dose of 4000 mg (4 grams) in 24 hours. 1, 2, 3

Standard Adult Dosing

• Single dose: 500-1000 mg taken orally, with 1000 mg being the optimal unit dose for maximum efficacy 1, 4
• Dosing interval: Every 4-6 hours as needed, with onset of action occurring within 15-30 minutes 1, 4
• Maximum frequency: 4 doses per 24 hours (when using 1000 mg doses) 1
• Absolute maximum daily dose: 4000 mg (4 grams) from all acetaminophen-containing products combined 1, 2, 3

Available Formulations

• Tablets and suppositories are commonly available in 500-1000 mg strengths 1
• Effervescent tablets provide more rapid absorption and faster onset of action compared to conventional tablets 4
• Intravenous formulation: 1 gram every 6 hours for critically ill patients 1

Critical Safety Limits

Exceeding 4000 mg daily can cause severe hepatotoxicity, liver failure, and death. 2, 3 Key safety considerations include:

• Never exceed 6 doses in 24 hours or take more than 4000 mg total 3
• Avoid combining with other acetaminophen-containing products (including prescription combinations with opioids like codeine) 5, 3
• Limit alcohol consumption to fewer than 3 drinks daily while using paracetamol 3
• For chronic use, consider limiting to 3000 mg daily to reduce hepatotoxicity risk 5

Special Population Dosing

Patients with Liver Disease

• Use 2000-3000 mg maximum daily in patients with cirrhosis due to prolonged half-life and metabolic impairment 5, 6
• Paracetamol is contraindicated in hepatic insufficiency 4

Elderly Patients (≥60 years)

• Standard dosing (up to 4000 mg daily) is appropriate for most older adults with normal organ function 6
• No routine dose reduction is necessary based on age alone 6
• The maximum single dose remains 1000 mg 2

Patients with Renal Disease

• Standard dosing is generally safe in chronic renal insufficiency without dose adjustment 4, 6

Clinical Context for Use

Mild Pain (WHO Step I)

• Paracetamol is first-line therapy for mild pain (numerical pain score 1-4) 1, 5
• Effective for osteoarthritis, low back pain, and general acute pain 1, 5

Moderate Pain (WHO Step II)

• For moderate pain (score 5-7), paracetamol can be combined with weak opioids (codeine, tramadol) up to maximum 4000 mg paracetamol daily 1
• When combined with NSAIDs, paracetamol enhances analgesic effect 4

Fever Management

• Paracetamol is effective for fever reduction, though evidence for improved neurological outcomes in stroke patients is lacking 1
• Doses of 3900-6000 mg daily have been studied for temperature reduction in hospitalized patients 1

Common Pitfalls to Avoid

• Unintentional overdose from multiple products: Many prescription and over-the-counter medications contain acetaminophen; always verify total daily intake 5, 3
• Subtherapeutic dosing: Using doses below 1000 mg may provide inadequate analgesia for moderate pain 1, 4
• Prolonged use without monitoring: For use beyond 10 days for pain or 3 days for fever, physician consultation is required 3
• Ignoring early toxicity signs: Nausea, vomiting, abdominal pain, and elevated liver enzymes (AST/ALT) warrant immediate medical attention 2, 5

Pediatric Dosing (for reference)

• 15 mg/kg per dose every 4-6 hours 7, 8
• Maximum 60 mg/kg/day (not to exceed adult maximum of 4000 mg) 4, 7
• This dose is significantly more effective than older recommendations of ≤10 mg/kg 7