Paracetamol Poisoning: Risk Factors, Clinical Features, Diagnosis, and Management

Introduction

Paracetamol (acetaminophen) overdose is a common cause of drug poisoning worldwide. Although paracetamol is widely used for pain relief and fever management, excessive intake can lead to severe toxicity and liver damage.

Risk Factors

• Intentional overdose due to self-harm or suicide attempts
• Unintentional excessive dosing, especially in children or elderly patients
• Chronic use of alcohol, which enhances hepatotoxicity
• Pre-existing liver disease
• Concomitant use of drugs that induce cytochrome P450 enzymes

Clinical Features

Paracetamol toxicity typically progresses through four stages:

1. Stage 1 (0-24 hours): Nausea, vomiting, diaphoresis, and pallor.
2. Stage 2 (24-72 hours): Hepatic injury begins, with right upper quadrant pain and elevated liver enzymes.
3. Stage 3 (72-96 hours): Severe hepatotoxicity, jaundice, coagulopathy, encephalopathy, and possible acute kidney injury.
4. Stage 4 (4-14 days): Recovery phase or progression to multi-organ failure.

Diagnosis

Diagnosis is primarily based on patient history, clinical symptoms, and laboratory investigations. Key assessments include:

• Serum paracetamol levels (especially within 4-24 hours of ingestion)
• Liver function tests (ALT, AST, bilirubin levels)
• Coagulation profile (INR, PT)

Management

• Administration of N-acetylcysteine (NAC) as the antidote to prevent hepatotoxicity.
• Activated charcoal for early decontamination if ingestion occurred within 1-2 hours.
• Supportive care including IV fluids, monitoring liver function, and addressing complications such as hepatic failure.
• Consider liver transplantation in cases of fulminant hepatic failure.

Prevention Strategies

• Public awareness campaigns on safe dosing practices.
• Regulation of paracetamol availability and packaging.
• Education for healthcare providers to recognize early toxicity signs.
• Improved mental health support to reduce intentional overdoses.

Public Health Implications

Paracetamol overdose remains a significant public health concern, requiring a multi-faceted approach to prevention and management.