From the Guidelines
Paracetamol overdose symptoms can be subtle and may not always be immediately apparent, but it is crucial to recognize them early to prevent severe liver damage and death. The symptoms of paracetamol overdose can be divided into stages, with the initial stage (within 24 hours) characterized by non-specific symptoms such as nausea, vomiting, abdominal pain, loss of appetite, and sweating 1. These early symptoms may seem mild or even absent, making the overdose particularly dangerous. After 24-72 hours, signs of liver damage emerge, including right upper quadrant pain, jaundice (yellowing of skin and eyes), confusion, and drowsiness. In severe cases, symptoms progress to include bleeding, hypoglycemia, kidney failure, and encephalopathy with cerebral edema. The toxic effects occur because paracetamol is metabolized in the liver, producing a harmful metabolite called N-acetyl-p-benzoquinoneimine (NAPQI) that depletes glutathione stores and damages liver cells 1. Some key points to consider in the management of paracetamol overdose include:
- The importance of prompt medical attention, as the antidote N-acetylcysteine (NAC) is most effective when given within 8-10 hours of ingestion
- The use of a nomogram to determine the risk of hepatotoxicity based on serum paracetamol concentration and time of ingestion
- The need for careful monitoring and treatment of patients with repeated supratherapeutic ingestions, who may have a worse prognosis than those with acute overdose 1. It is essential to note that treatment decisions are typically based on the amount ingested, time since ingestion, and blood paracetamol levels, and that without prompt treatment, severe liver damage or death can occur, even if initial symptoms seem mild.
From the FDA Drug Label
Warnings Liver warning This product contains acetaminophen Severe liver damage may occur if: an adult takes more than 6 doses in 24 hours, or greater than 4000 mg of acetaminophen, the maximum daily amount Overdose warning Taking more than the recommended dose (overdose) may cause liver damage. In case of overdose, get medical help or contact a Poison Control Center right away. (1-800-222-1222). Quick medical attention is critical for adults as well as children even if you do not notice any signs or symptoms. The symptoms and signs of paracetamol overdose are not explicitly listed, but it is mentioned that severe liver damage may occur.
- The label warns of liver damage in case of overdose, but does not provide specific symptoms or signs. It is recommended to seek medical help immediately in case of overdose, even if no signs or symptoms are noticed 2.
From the Research
Paracetamol Overdose Symptoms and Signs
- The symptoms and signs of paracetamol overdose are not explicitly stated in the provided studies, but the studies discuss the interventions and risk factors associated with paracetamol overdose 3, 4, 5, 6, 7.
- However, it can be inferred that hepatotoxicity, fulminant hepatic failure, and liver injury are potential consequences of paracetamol overdose, as these outcomes are frequently mentioned in the studies 3, 4, 6, 7.
Interventions for Paracetamol Overdose
- Activated charcoal seems to be the best choice to reduce the absorption of paracetamol, but its clinical benefits are unclear 3, 4, 6.
- N-acetylcysteine appears to be superior to placebo and has fewer adverse effects compared to dimercaprol or cysteamine, but its superiority to methionine is unproven 3, 4, 6.
- Gastric lavage, ipecacuanha, and supportive treatment may also be effective in reducing paracetamol absorption, but the evidence is limited and of low quality 6.
Risk Factors for Hepatotoxicity
- Male gender, alcohol abuse, and an ingested paracetamol dose are significant risk factors for hepatotoxicity in univariable analysis 7.
- However, the only significant risk factor in the multivariable model is the timespan from ingestion to hospital admission, with a delay in hospital admission resulting in a delayed administration of disease-specific treatment 7.