What is the maximum dose?

From the Guidelines

The maximum dose of the medication in question is 15 mg/kg per day, not to exceed 1.0 g/day, as recommended for adults, and 15-30 mg/kg per day, not to exceed 1 g/day, for children, as stated in the American Thoracic Society guidelines 1. When considering the maximum dose, it's crucial to take into account the patient's age, weight, and renal function, as these factors can significantly impact the medication's safety and efficacy.

• For adults, the maximum dose is 15 mg/kg per day, which should not exceed 1.0 g/day, and is usually given as a single daily dose five to seven times a week, with a reduction to two or three times a week after the first 2–4 months or after culture conversion, depending on the efficacy of the other drugs in the regimen 1.
• For children, the maximum dose ranges from 15-30 mg/kg per day, not to exceed 1 g/day, and can be administered as a single daily or twice weekly dose 1.
• It's also important to note that for persons greater than 59 years of age, the dose should be reduced to 10 mg/kg per day, and for those with renal insufficiency, the dosing frequency should be reduced to 12–15 mg/kg two or three times per week 1. In contrast to another study that suggests a maximum dose of 10 mg/kg (600 mg) once weekly during the continuation phase of treatment for adults, and does not approve the drug for use in children 1, the guidelines from the American Thoracic Society provide more detailed and specific dosing recommendations, making them a more reliable source for determining the maximum dose 1.

From the FDA Drug Label

Do not exceed 3200 mg total daily dose. The maximum dose is 3200 mg per day.

• This is the total daily dose that should not be exceeded. 2

From the Research

Maximum Dose of Acetaminophen

• The maximum recommended dose of acetaminophen is 2 g/d in patients with liver disease, as stated in the study 3.
• This dose is considered safe and is a preferred analgesic/antipyretic due to the absence of platelet impairment, gastrointestinal toxicity, and nephrotoxicity associated with nonsteroidal anti-inflammatory drugs 4.
• However, it is essential to note that the maximum dose may vary depending on individual factors, such as the severity of liver disease and other health conditions.
• The study 5 also suggests that the short-term use of acetaminophen at reduced doses (2 grams daily) appears to be safe in patients with non-alcoholic liver disease.
• Another study 6 mentions that the maximum recommended dosage can induce hepatic cytolysis in some individuals, highlighting the need for cautious use and monitoring.

Factors Affecting Maximum Dose

• The presence of chronic liver disease, such as nonalcoholic fatty liver disease (NAFLD), may increase the risk of acetaminophen-induced liver injury 6.
• Obesity itself does not seem to be associated with a higher risk of acetaminophen-induced liver injury, but the presence of NAFLD can increase the risk 6.
• The study 7 reports a case of moderate liver enzyme elevation after acute acetaminophen overdose, despite an initial undetectable acetaminophen level and normal liver enzymes, highlighting the importance of monitoring liver function in patients taking acetaminophen.
• The pharmacokinetic parameters of acetaminophen are altered in patients with severe liver disease, which may affect the maximum safe dose 5.