Acetaminophen Overdose Overview
What is the generally considered safe daily ingestion limit of acetaminophen (APAP)?
≤ 4 g/day of APAP is generally considered safe.
Clinical Features of APAP Overdose
What are the stages of acute APAP toxicity?
Stage 1: Asymptomatic; Stage 2: Nausea, vomiting, RUQ pain; Stage 3: Maximal liver toxicity; Stage 4: Recovery phase.
N-acetylcysteine (NAC) as Antidote
What is the mainstay of therapy for APAP overdose?
The mainstay of therapy is the antidote N-acetylcysteine (NAC).
Acute vs. Chronic APAP Ingestion
What is the definition of chronic APAP overdose?
Chronic APAP overdose is defined as repeated supratherapeutic ingestion over a period of > 24 hours.
Diagnosis of Acetaminophen Overdose
What is the significance of serum APAP levels in diagnosing overdose?
Serum APAP levels help guide management and determine the need for NAC therapy.
Acute vs. Chronic APAP Ingestion
What is the minimum toxic dose of APAP for healthy adults?
The minimum toxic dose for healthy adults is 7.5 g/day.
Management Strategies for APAP Overdose
What should be done if a patient presents with massive APAP overdose?
Consult toxicology, consider intubation, administer NAC, and admit to the ICU for ongoing management.
Epidemiology of APAP Overdose
What is the leading cause of acute liver failure in the US?
APAP overdose is the leading cause of acute liver failure in the US.
N-acetylcysteine (NAC) as Antidote
What are the indications for administering NAC?
NAC is indicated for acetaminophen toxicity, acute ingestion with serum concentration above the treatment line, and chronic ingestion with elevated AST.
Clinical Features of APAP Overdose
What are the early clinical features of acute APAP overdose?
Individuals may be asymptomatic or have nausea, vomiting, and lethargy.
Monitoring and Disposition of Patients
What should be monitored in patients with acute liver failure due to APAP overdose?
Monitor AST, ALT, INR, lactate, and creatinine levels.
N-acetylcysteine (NAC) as Antidote
What are the contraindications for NAC administration?
There are no contraindications for NAC; a previous anaphylactoid reaction is not a contraindication.
Management Strategies for APAP Overdose
What is the role of activated charcoal (AC) in APAP overdose management?
Single-dose activated charcoal may be indicated for gastrointestinal decontamination.
Pathophysiology of APAP Toxicity
What happens to glutathione reserves during APAP overdose?
Glutathione initially inactivates NAPQI, but its reserves are eventually depleted, leading to NAPQI accumulation.
Diagnosis of Acetaminophen Overdose
What is the significance of the Rumack-Matthew nomogram?
The Rumack-Matthew nomogram is used to determine the risk of severe hepatotoxicity in acute APAP overdose based on serum APAP level and time since ingestion.
