Acetaminophen is an effective and safe painkiller. However, if taken in excess it can be fatal. Taking an acetaminophen overdose overwhelms the liver's ability to process the drug. The excess acetaminophen is then processed into toxic chemicals, which can kill liver cells. If enough cells are killed the patient can die from liver failure. Fortunately, a drug called N-acetylcysteine (NAC) can be given as an effective antidote for acetaminophen poisoning if the patient is treated within 12 hours of the overdose.
Doctors from the US analysed the medical records of 93 patients who were hospitalised as a result of an acetaminophen overdose, 80 were classed as suicidal with the remainder having accidentally overdosed in attempt to relieve their pain. They found that those patients who had accidentally overdosed fared less well than those who attempted suicide.
This was surprising given that the levels of acetaminophen were much lower in the patients who had taken the overdose by accident compared with those who had deliberately overdosed. Analysis of the patient's case histories revealed that those patients who overdosed by accident waited longer before going to hospital. The effectiveness of NAC, as an antidote to acetaminophen is reduced if it cannot be given at least 12 hours after an overdose is taken.
It was also shown that the patients who overdosed by accident and were more likely to heavy drinkers. Acetaminophen toxicity is made worse by alcohol consumption because the liver is a
Contact: Gordon Fletcher