Fortunately, N-acetylcysteine (NAC) is a safe and effective antidote which if used correctly prevents serious hepatic injury after paracetamol overdose.
There may be no symptoms for the first day. A feeling of sickness (nausea) and being sick (vomiting) may occur a few hours after taking the overdose. After 24 hours there may be pain under the ribs on the right side (where the liver is) and there may be yellowing of the whites of the eyes and the skin (jaundice).
Acetylcysteine is highly effective in preventing severe liver injury if administered within 8–10 h after a significant paracetamol overdose [Prescott et al. 1979].
Serious toxicity may occur in patients who have ingested > 150 mg/kg in any 24 hour period. Rarely, toxicity may occur for ingestions between 75-150 mg/kg. Doses consistently < 75 mg/kg in any 24 hour period are unlikely to be toxic.
Go to the nearest emergency department (A&E) if:
you have stomach pain. you feel sick (nausea) or are being sick (vomiting) your skin or eyes look yellow (jaundice)
If you take too much
Taking 1 or 2 extra tablets is unlikely to harm you. Do not take more than 8 tablets in 24 hours. Taking too much paracetamol can be dangerous and you may need treatment. Too much paracetamol can cause liver damage.
Paracetamol toxicity, albeit accidental or intentional overdose, is an ongoing global problem that continues to result in cases of hepatotoxicity, acute liver failure, and even irreversible liver injury necessitating liver transplantation.
Its effects usually last for about 4 to 6 hours.
Paracetamol is readily absorbed from the gastrointestinal tract with peak plasma concentrations occurring about 30 minutes to 2 hours after ingestion. It is metabolised in the liver (90-95%) and excreted in the urine mainly as the glucuronide and sulphate conjugates. Less than 5% is excreted as unchanged paracetamol.
Paracetamol can take up to an hour to work. Paracetamol is safe to take during pregnancy and while breastfeeding, at recommended doses. It may not be safe for you to drink alcohol with paracetamol if you have certain health conditions, such as liver problems. Check the leaflet that comes with your medicine.
Symptoms and Signs of Acetaminophen Poisoning
), include anorexia, nausea, vomiting, and right upper quadrant abdominal pain. Renal failure and pancreatitis may occur, occasionally without liver failure. After > 5 days, hepatotoxicity resolves or progresses to multiple organ failure, which can be fatal.
Just a few paracetamol tablets over the recommended dose can potentially cause fatal liver damage, and there may be no symptoms until it is too late for treatment to help. There is an antidote for paracetamol poisoning and it is most effective within eight hours of the overdose, so getting help early is essential.
Symptoms of Acetaminophen Poisoning
In stage 1 (after several hours), the person may vomit but does not seem ill. Many people have no symptoms in stage 1. In stage 2 (after 24 to 72 hours), nausea, vomiting, and abdominal pain may develop. At this stage, blood tests show that the liver is functioning abnormally.
However, repeatedly taking more than the recommended dose or overdosing on paracetamol can cause serious injury to the liver and even death. The recommended maximum dose of paracetamol for an adult (or child over 12 years) is 4g in any 24-hour period (equivalent to 8 x 500mg tablets).
You should not take more than 8 normal strength tablets in 24 hours (4,000mg). If levels exceed the above paracetamol can cause liver damage (hepatotoxicity) if you take larger doses than recommended. Adults must not take more than 4000 mg in a 24-hour period.
Summary. Paracetamol overdose may occur after excessive ingestion of paracetamol or paracetamol-containing medication as an acute or staggered overdose, or therapeutic excess. Patients are often asymptomatic or have only mild gastrointestinal symptoms at initial presentation.
The recommended paracetamol dosing for adults and children 12 years and over is 500 to 1000mg every four to six hours as necessary, with a maximum of 4000mg in any 24 hour period.
If you take too much Paracetamol your liver may not be able to metabolise it efficiently and this could make you extremely unwell. Paracetamol overdose can lead to liver failure in some people and this is why you need to take careful note of this advice.
Liver failure can happen if you take too much paracetamol and don't get help. This can lead to death. Symptoms of paracetamol overdose are: abdominal pain, nausea, vomiting.
Paracetamol/Acetaminophen
Recommended paracetamol dose in adults = 4g or 75mg/kg in 24h. Overdose = ingestion >75mg/kg. > 150mg/kg = Lethal.
Reversing liver damage Liver Basics
For example, an overdose of acetaminophen (Tylenol) can destroy half of a person's liver cells in less than a week. Barring complications, the liver can repair itself completely and, within a month, the patient will show no signs of damage.