A large study found that soluble paracetamol that contains salt as a “hidden” ingredient can be linked to an increased risk of heart disease and death.
The researchers caution that people often take soluble pain medications without knowing they contain sodium, which drug manufacturers add to help the tablets dissolve more easily in water.
This lack of awareness, they said, means that paracetamol users are likely to exceed the recommended daily salt intake of 2g. Some can cross this threshold through medication alone, as some cereals contain up to 0.44g of salt.
And although most forms of paracetamol do not contain sodium, experts suggest that those who do should issue a health warning on drug packages.
Professor Zhao Tsing, of Central South University in Changsha, China, who led the study, believes that doctors should always prescribe salt-free drugs to reduce risks.
He explained: “People should pay attention not only to the intake of salt in their food but also not to overlook the intake of hidden salt from medicines.”
Professor Tsing added: “Our results suggest that the safety profile of effervescent and soluble paracetamol be reconsidered.”
The study, published in the European Heart Journal, was based on an analysis of data collected from 790 British surgeries between 2000 and 2017.
The researchers looked at a group of 300,000 patients between the ages of 60 and 90, half of whom had high blood pressure. Some received sodium-containing paracetamol, while the rest received sodium-free medication.
Among the high blood pressure group, the risk of heart failure or stroke was 5.6% for those who took paracetamol with salt for a year and 4.6% for those who received the sodium-free medication.
Similarly, for those without high blood pressure, the risk of heart disease was higher among those who took salt-containing paracetamol, the risk being 4.4% for those who took paracetamol with sodium, and 3.7% for those who took sodium-free paracetamol.
The international researchers found that the chance of death in the follow-up period was greater for those taking paracetamol with salt.
Commenting on the study, two academics from Australia’s George Institute of Global Health said the risks posed by such drugs were increasing as “effervescent” pills became more common.
The team added: “There is an urgent need to protect consumers from these risks. The most reasonable and effective strategy would likely be mandatory labeling of all medications containing significant amounts of sodium with a warning label on the front of the package.”
However, Professor Sir Nilesh Samani, medical director of the British Heart Foundation, said the study was limited because it did not contain data on how much salt people were consuming through their diets.
“It is also important to remember that such observational studies can only show an association, rather than prove cause and effect.”
