By Pat Anson PNN Editor

Long-term use of the pain reliever acetaminophen has long been associated with liver, kidney, heart and blood pressure problems.  A new study has also found that some acetaminophen tablets are so loaded with salt that they significantly raise the risk of a heart attack or stroke in as little as one year.

At issue are dissolvable acetaminophen tablets that are mostly used to treat cold and flu symptoms, as well as minor aches and pains. The tablets quickly dissolve in water because of their high salt (sodium) content, creating a fizzy, effervescent drink that is absorbed more quickly in the digestive system than a standard tablet.

Some of the fizzy tablets contain as much as 440 milligrams of sodium per pill. A recommended daily dose of two tablets taken four times a day adds up to over 3,500 milligrams – more sodium than three McDonald’s Big Macs – and nearly double the daily amount recommended for healthy adults.

Since high salt content has long been associated with cardiovascular problems, a team of researchers looked at the health records of 300,000 people enrolled in Britain’s National Health Service who were prescribed acetaminophen (paracetamol) to see what impact the medications may have.

Their findings, recently published in the European Heart Journal, showed that patients with a history of high blood pressure (hypertension) taking fizzy acetaminophen tablets were up to 45% more likely to suffer a heart attack, stroke or heart failure within a year. Just one prescription for the tablets increased their risk of dying by 177 percent, and those with five or more prescriptions were 264% more likely to die.

The risk of a heart attack, stroke or death for patients without high blood pressure also rose with a prescription for fizzy acetaminophen, but to a lesser degree.

“The direct message from this study is clear—there are likely to be millions of people worldwide taking paracetamol on a daily basis in a ‘fast-acting’ effervescent or soluble formulation who are increasing their risks of cardiovascular disease and premature death,” wrote Aletta Schutte, PhD, and Bruce Neal, PhD, in an accompanying editorial.

“Fortunately, only a small proportion of paracetamol formulations contain sodium but, with ‘fast-acting’ and ‘fizzy’ medications increasing in popularity, the adverse effects of medication-related sodium intake look set to rise rather than fall.”

The risk isn’t limited to fizzy tablets with acetaminophen. Other effervescent medications containing aspirin, ibuprofen and even vitamins also contain high levels of sodium.  

With or without salt, long-term acetaminophen use can be risky. A recent study at the University of Edinburgh found that acetaminophen significantly raised the risk of heart disease and stroke in people with high blood pressure. Researchers said the increased risk of cardiovascular problems was similar to that seen with non-steroidal anti-inflammatory drugs (NSAIDs).

Acetaminophen is the most widely used over-the-counter pain reliever in the world — and is the active ingredient in Tylenol, Excedrin, and hundreds of pain medications. But a 2021 review found little or no evidence to support the use acetaminophen for most pain conditions.