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Sodium in effervescent or soluble paracetamol: a hidden danger

By Dr Emily Lathlean MB BS, FRACGP
Use of paracetamol containing sodium is linked with increased risks of cardio­vascular disease (CVD) and all­-cause mortality compared with non­-sodium­-containing formulations, a study published in European Heart Journal has found.

‘For many years, epidemiolo­gical and clinical trial evidence inferring serious harms of excess dietary sodium consumption on human health has accumulated,’ wrote Professor Aletta Schutte, a UNSW SHARP Professor and Principal Theme Lead of Cardiac, Vascular and Metabolic Medicine in the Faculty of Medicine and Health at UNSW Sydney, and Professor Bruce Neal, Professor of Medicine at UNSW, Sydney, and Executive Director of The George Institute Australia, in their accompanying editorial. ‘... National and international blood pressure guidelines, as well as the World Health Organization, recommend that daily sodium intake should not exceed 2000 mg.’

The study authors noted that a maximum daily dose (4g/day) of effervescent and soluble formulations of paracetamol contained 3.5g of sodium, already exceeding the daily sodium intake advised by guidelines.

Using an electronic medical record database of UK GPs, two large cohort studies were conducted involving almost 300,000 individuals aged between 60 and 90 years, with and without hypertension. Participants were excluded if they had been prescribed paracetamol during the year prior or had a history of CVD. Individuals who initiated either sodium­-containing paracetamol (i.e. in effervescent or soluble formulation) or non­-sodium­-containing paracetamol (i.e. in tablet, oral suspension or capsule formulation) were identified and outcomes assessed over one­-year’s follow up.

In both groups, the one-year risk of incident CVD was higher among individuals who had initiated sodium­-containing paracetamol than in those who had initiated non­-sodium­-containing paracetamol (in those with hypertension 5.6%vs 4.6%, respectively; hazard ratio [HR], 1.59; and in those without hypertension 4.4% vs3.7%, respectively; HR, 1.45).

The one­-year risk of all­-cause mortality was also higher in those taking sodium-­containing paracetamol than in those taking non­-sodium­-containing­ paracetamol, regardless of hypertension status (in those with hypertension 7.6% vs 6.1%, respectively; in those without hypertension 7.3% vs 5.9%, respectively).

‘The results are compelling,’ wrote Professor Schutte and Professor Neal, who also called for caution regarding other sodium­-containing medications and the need to raise awareness among practitioners and the general public about the harms of such medications. ‘Efferve­scent and soluble forms of paracetamol is not the only example of a medication that can be delivered with very different levels of sodium content ... The widespread use of effervescent medication in the general population, and the enormous doses of sodium that can be consumed inadvertently by unsuspecting consumers requires urgent action.’
Eur Heart J 2022; https://doi.org/10.1093/eurheartj/ehac059.
Eur Heart J 2022; https://doi.org/10.1093/eurheartj/ehab888.