From the Guidelines
The maximum daily dose of intravenous (IV) paracetamol (acetaminophen) for adults with normal liver function is 4 grams per day, as recommended by the most recent guidelines 1. This dose is typically administered as 1 gram (1000 mg) every 6 hours, with a minimum interval of 4 hours between doses. For patients weighing less than 50 kg, the dose should be reduced to 15 mg/kg per dose (not exceeding 750 mg per dose) with the same frequency, as suggested by the ERAS society recommendations 1. It's essential to include the IV paracetamol dose when calculating the total daily paracetamol intake if the patient is transitioning to or receiving concurrent oral paracetamol. The 4-gram daily limit is established to prevent hepatotoxicity, as paracetamol is metabolized primarily by the liver, and excessive doses can deplete glutathione stores, leading to accumulation of the toxic metabolite N-acetyl-p-benzoquinone imine (NAPQI), which can cause liver damage, as noted in the NCCN clinical practice guidelines 1. Key points to consider when administering IV paracetamol include:
- Regular dosing up to 15 mg/kg every 6 h (with a maximum of 4 g per 24 h) is a good analgesic base in all patients except those with liver dysfunction 1
- The use of non-steroidal anti-inflammatory drugs (NSAIDs) in the perioperative period should be used with caution due to the risk of platelet dysfunction with subsequent bleeding and effect on renal blood flow 1
- Intravenous NSAIDs are available and can be introduced postoperatively once renal function is not impaired, and the risk of bleeding has passed 1
From the FDA Drug Label
Adults and Adolescents Weighing 50 kg and Over: 1000 mg every 6 hours or 650 mg every 4 hours to a maximum of 4000 mg per day. Adults and Adolescents Weighing Under 50 kg: 15 mg/kg every 6 hours or 12. 5 mg/kg every 4 hours to a maximum of 75 mg/kg per day. The maximum IV paracetamol dose per day for a patient with normal liver function is 4000 mg per day for adults and adolescents weighing 50 kg and over, and 75 mg/kg per day for adults and adolescents weighing under 50 kg 2.
From the Research
Maximum IV Paracetamol Dose Per Day for Normal Liver
- The maximum IV paracetamol dose per day for patients with normal liver function is not explicitly stated in the provided studies.
- However, according to the study 3, the short-term use of paracetamol at reduced doses (2 grams daily) appears to be safe in patients with non-alcoholic liver disease.
- Another study 4 recommends reduced doses of 2-3 grams daily for long-term use of paracetamol in patients with chronic liver disease.
- It is essential to note that these recommendations are for patients with liver disease, and the maximum safe dose for patients with normal liver function may be higher.
- The study 5 discusses the risks of paracetamol-induced liver injury, but does not provide specific guidance on the maximum safe dose for patients with normal liver function.
- The studies 6 and 7 focus on the prognosis and diagnosis of paracetamol-induced acute liver failure, but do not provide information on the maximum safe dose for patients with normal liver function.