- Babies given paracetamol were more likely to have asthma by age 3
- Taking drug during pregnancy increases risk of asthma developing later
- Experts: Drug causes free radical molecules to trigger allergic reaction
- Researchers also found a link between ibuprofen in infanthood and asthma
Babies who are given paracetamol are nearly a third more likely to develop asthma, researchers have found.
Taking paracetamol during pregnancy also increases the chance of the unborn child later becoming asthmatic, according to the Bristol University study.
Paracetamol is the most commonly used painkiller for babies, and is used in medicines such as Calpol and Disprol as well as low-dose painkiller tablets.
Babies who are given paracetamol are nearly a third more likely to develop asthma, a study has found
The Bristol team and scientists from Oslo University examined data from 114,500 pregnancies, tracking the children until the age of seven.
They found that taking paracetamol by mothers during pregnancy and by babies in infanthood was linked to the development of asthma by the age of three.
The scientists, whose findings were published in the International Journal of Epidemiology, tested their theory against the idea that the asthma was caused by the medical complaint for which the person was taking paracetamol.
Even after that idea had been taken into account, a strong link to paracetamol remained.
The scientists suspect that paracetamol induces ‘oxidative stress’, in which unstable molecules known as free radicals trigger an allergic response.
The scientists found that children given paracetamol during infancy were 29 per cent more likely to be diagnosed with asthma by the age of three, with a similar rate at age seven.
Mothers who had taken paracetamol during pregnancy had a 13 per cent increased chance of their baby developing asthma by the age of three, a rate that doubled to 27 per cent by the age of seven.
Taking paracetamol during pregnancy also increases the chance of the unborn child later becoming asthmatic
The association was similar whether used for influenza, fever, or pain.
The team also examined the link between asthma and ibuprofen taken during pregnancy.
They found that mothers who had taken ibuprofen while pregnant were more likely to have a child with asthma at the age of three – but this link was less certain, and had disappeared by the age of seven.
The results showed that 5.7 per cent of the children had asthma at age three, and 5.1 per cent had asthma at age seven.
Researcher Dr Maria Magnus, of Bristol University, said: ‘Uncovering potential adverse effects is of public health importance, as paracetamol is the most commonly used painkiller among pregnant women and infants.’