Is your medicine raising your risk of stroke? In a new report from the University of Dundee and University College London, researchers show that taking the maximum daily dose of some medications may cause you to exceed the recommended daily sodium intake –– even if you’re following a low sodium diet otherwise. As excessive sodium intake has been associated with an increased risk of cardiovascular events, the study authors recommend new warning labels on many medicines, particularly painkillers. 

Prevailing research implicates high amounts of salt in a range of adverse events and conditions, including stroke, heart attack, and hypertension. However, pharmaceutical companies typically add significant levels to some of their products, as it is thought to improve absorption into the body. This is particularly common when synthesizing soluble, effervescent, and dispersible painkillers like ibuprofen and aspirin. 

"We were surprised at how much salt there was in some tablets. All the foods we buy we can find out in intricate detail how much sodium there is but we can't do that with medicines," Thomas Macdonald of the University of Dundee told The Daily Mail. "It's an avoidable risk and it's a cardiovascular risk which is the commonest cause of death in Britain. If you take these drugs every day it would be better for your health to take the normal versions, not the soluble ones."

In the report, the researchers compared the risk of cardiovascular events in patients taking medication high in sodium with that of patients taking non-sodium versions of the same drug. Using surveillance tables published between 1987 and 2010, the team tracked the health outcomes of over 1.2 million British patients for an average period of seven years. Factors like body mass index (BMI), smoking habits, and alcohol intake were also taken into account. 

The team found that patients who took soluble, dispersible, or effervescent medication high in sodium had a 16 percent increased risk of heart attack, stroke, or vascular death compared to patients who took non-sodium medication. “This is an important reminder for doctors and patients to carefully consider the risks and benefits of soluble or effervescent medicines at the time of prescription,” Mike Knapton of the British Heart Foundation said of the results. 

That said, the study focused primarily on patients with chronic conditions, and most of them consumed the maximum dose on a daily basis. There is, in other words, no reason to panic if you take a dissolvable aspirin once or twice a week. ”It’s important to remember that this research applies to people who are taking these medicines every day –– this does not mean that occasional use could damage your heart health,” Knapton told reporters.