Paracetamol Overdose Flashcards
What is the most common Overdose seen in the UK?
Paracetamol overdose
What does Risk Assessment of a Paracetamol Overdose pt involve? (7 things)
- Date of ingestion (was there a delay in CF?)
- Timing of ingestion (single overdose / staggered)
- Time of last ingestion
- Weight
- Pregnancy
- Total amount ingested
- Current suicidal risk
If a pt is above 110kg, what should you do for weight calculations of meds?
Use 110kg as maximum weight
How does Pregnancy affect weight calculations of meds? (2 things)
- Use Pre-preg weight to determine toxicity
- Current weight for Tx
What should you consider if a pt has a high current suicidal risk?
Have a MH nurse stay with them
What ACUTE dose of Paracetamol will cause Toxicity?
Over 75mg / kg
What STAGGERED dose of Paracetamol will cause Toxicity?
Over 150mg / kg over 24 hours
What ACUTE dose of Paracetamol will kill you (or haver serious fx)? (2 things)
- 150mg / kg
- 12g +
If timing of ingestion is unknown, how should you treat the pt?
As staggered overdose
What are the RF for developing toxicity with Paracetamol overdose? (2 things)
- Liver enzyme-inducing drugs
- Malnourished
What are some liver enzyme-inducing drugs that increase the risk of developing Toxicity with Paracetamol Overdose? (5 things)
- Rifampicin
- Phenytoin
- Carbamazepine
- Chronic alcohol excess (not ACUTE tho)
- St John’s Wort
How long does it take Paracetamol to reach peak Conc once ingested?
4 hours
What is the half life of Paracetamol?
2 hours
How early after Paracetamol ingestion can levels be measured?
4 hours after last ingestion
(can’t interpret levels before 4 hours)
How long after ingestion can Paracetamol levels be detected for?
24 hours
(but any detectable level after 16 hours is concerning)
What Toxic metabolite is Paracetamol converted to?
NAPQI
What are the bad things NAPQI can lead to? (3 things)
- Oxidative damage
- Mitochondrial dysf
- Hepatocellular injury