Repeatedly taking slightly too much paracetamol over time can cause a dangerous overdose that is difficult to spot, Edinburgh University researchers have warned.
Patients may not come to hospital reporting the overdose but due to feeling unwell. This “staggered overdose” needs to be recognized and treated rapidly because these patients are at even greater danger than people who take single overdoses, they write in the British Journal of Clinical Pharmacology online.
The researchers analysed data on 663 patients admitted with paracetamol-induced liver injury. They found 161 had taken a staggered overdose, usually to relieve a variety of common pains, such as abdominal or muscular pains, headache and toothache.
“These staggered overdose patients were more likely to have liver and brain problems, require kidney dialysis or help with breathing and were at a greater risk of dying than people who had taken single overdoses,” said the authors.
- Craig D G N et al (2011) Staggered overdose pattern and delay to hospital presentation are associated with adverse outcomes following paracetamol-induced hepatotoxicity. British Journal of Clinical Pharmacology. DOI: 10.1111/j.1365-2125.2011.04067.x