Although doctors know that Paracetamol (acetaminophen) can cause acute liver failure, researchers from Edinburgh University have discovered that it can also trigger multi-organ collapse and death.
The damage can be caused by overdosing with just a couple of extra tablets a day for a few days or weeks, they have discovered.
This 'staggered overdose' is easily done, say the researchers, especially among people who are suffering chronic pain, and yet is often not picked up by doctors. Even blood tests cannot detect signs of any damage.
Staggered overdose - which can happen over days, weeks or months - is usually more dangerous than a sudden massive overdose.
Paracetamol has been used since the 1950s under a variety of marketing names, most commonly Panadol and Tylenol.
(Source: British Journal of Clinical Pharmacology, 2011; 71: 273-82).