P-Paracetamol
Paracetamol is a non-opioid analgesic and antipyretic agent used to treat fever and mild to moderate pain. To analyze its concentration in the blood and identify a potential overdose, a P-Paracetamol blood test can be performed. Blood samples are usually taken at least 4 hours after the last intake of a medication containing paracetamol. The timing of the sample is crucial for accurately interpreting the concentration in relation to toxicological guidelines.
Analysis of P-Paracetamol
In the analysis of P-Paracetamol, the concentration of the drug in plasma or serum is measured. The analysis is conducted using methods such as high-performance liquid chromatography (HPLC) or immunological techniques. These methods ensure precise and reliable results, which are critical for assessing the risk of toxic effects.
Are high concentrations of paracetamol dangerous?
Paracetamol has low acute toxicity at therapeutic doses, but in cases of overdose, part of the drug is converted to a toxic metabolite (NAPQI) that can cause severe liver damage. Symptoms are often absent initially, but at higher doses, signs of liver injury can appear after 24-36 hours, with rising liver enzymes (ALAT and ASAT). Maximum liver damage typically occurs after 72-96 hours. Severe poisoning can lead to fulminant liver failure, coagulation disorders, encephalopathy, and circulatory collapse.
Symptoms of paracetamol overdose
Nausea and vomiting may occur within a few hours after an overdose. These symptoms often subside within a day. Later, abdominal pain and signs of liver injury, such as elevated transaminases and increased prothrombin complex (PK-INR), may develop after 1-2 days. In severe poisoning, kidney impairment, hypoglycemia, metabolic acidosis, and altered mental status may occur. Early mental status changes are sometimes seen with very high serum concentrations of paracetamol (>4000 µmol/L).
Reference ranges for P-Paracetamol
- Not detectable: Less than 33 nmol/L
- Toxic concentration: Over 300 nmol/L (depending on the time since ingestion)
In suspected overdose cases, it is important to interpret the P-Paracetamol level in relation to the time of ingestion. Nomograms (e.g., Rumack-Matthew nomogram) are used as needed to assess the risk of liver damage and the need for treatment.
Acute treatment for paracetamol poisoning
Intravenous treatment with acetylcysteine (NAC) is the first-line therapy in suspected or confirmed toxic paracetamol overdose. Acetylcysteine acts as a precursor to glutathione, neutralizing the toxic metabolite NAPQI. Treatment should begin immediately in suspected overdose cases, especially if P-Paracetamol cannot be analyzed within 8 hours.
- Adults and children over 6 years: Treatment is recommended for ingestion exceeding 150 mg/kg body weight.
- Children under 6 years: Treatment is recommended for ingestion exceeding 200 mg/kg body weight.
Regular monitoring of P-Paracetamol and liver function tests (ALAT, ASAT, PK-INR) is necessary during the treatment process.