A recently published study suggests that giving young children paracetamol too often increases their risk of developing the three atopic illnesses asthma, eczema and hay fever. Children are also, of course, exposed to paracetamol in products like Calpol (see ‘Beware of Calpol’ in Green Health Watch 28), Benilyn, Medinol, Day Nurse and Lemsip.

The first study,[1] covering 200,000 children in 31 countries, found that:

• children who had been given a paracetamol product at least once during the first month of life had been 46% more likely to have developed asthma, 48% more likely to have developed rhinoconjunctivitis (similar to hay fever), and 35% more likely to have developed eczema, by the ages of six and seven
• children whose parents said that they had been given a paracetamol product at least once a month during the last twelve months (the researchers’ definition of ‘current use’) had been between one and a half and three times more likely to have developed asthma, depending on the frequency of usage. They had also been twice as likely to have developed rhinoconjunctivitis and three times as likely to have developed eczema

Lead researcher Professor Richard Beasley accepted that paracetamol was the safest known pain-killing drug for children but was concerned that it was being both wrongly and excessively used. Originally the only intended use of paracetamol for children was to bring down high fever, he said. Although these findings confirm those of earlier studies, he accepts that a link between paracetamol and atopic illness has not been proved definitively and calls for more research urgently.

Ed.- (i) Whether by accident or design, another study [2] linking paracetamol to asthma (but this time in adults) was published in September 2008. It found a threefold increased risk of asthma in regular paracetamol users. Again, not proof that paracetamol causes asthma - it might have been that asthmatic attacks had led to an increased use of the painkiller, but it makes you think.

And yet another September 2008 study linked a different painkiller, acetaminophen, to respiratory symptoms in the first year of life. Apparently foetuses exposed to acetaminophen taken by their mothers during the fourth to ninth month of pregnancy (but not the first three) almost doubled their risk of developing regular wheezing sufficiently severe to disturb sleep.
Funny how things come in threes!

(ii) In 1975 a team of researchers reported in The Lancet that paracetamol was one of the commonest causes of liver failure in the UK. The journal’s editor agreed that the painkiller should be withdrawn as soon as a safer alternative could be found, commenting: “If (paracetamol) had been discovered today it would not have been approved by the Committee on Safety of Medicines and would certainly never have been freely (available) without prescription”.

Paracetamol is still on chemists’ shelves, advertised as a ‘safe’ painkiller on the basis that, unlike aspirin, it does not cause stomach bleeding. The recommended maximum daily dose is 4gm, only just below the 6.3gm dose which will damage the liver but take 4-6 days to show. Taking 6.3gm four days in a row, unaware of the danger, can lead to liver failure. Any overdose must be treated immediately, no matter how well the person appears. Paracetamol may also cause kidney failure, especially if part of a combined paracetamol/aspirin painkiller. The aspirin reduces blood flow to the kidney making it less tolerant to paracetamol. It is now generally accepted that ‘cocktail painkillers’ like Calpol are more toxic than the total of their individual parts.

The antidote to paracetamol poisoning is cysteamine hydrochloride, but this must be administered within 8-10 hours to prevent severe damage. Cysteamine hydrochloride must never be administered if severe liver or kidney damage has already been established.

(iii) Both paracetamol and paracetamol cocktails like Calpol can be fatal for children with liver or kidney problems. Never give them without your GP’s agreement.

(iv) Paracetamol was brought in in 1974 to replace phenacetin, which certainly caused kidney disease. It was an odd decision. Phenacetin breaks down in the kidneys into paracetamol within two hours of being taken.