Acetaminophen Side Effects May Increase Risk of Kidney Damage, Death Risks: Study

The findings of a new study suggest that side effects of acetaminophen, the active ingredient found in Tylenol and a many other commonly-used painkiller, may have more health consequences than previously believed. 

In the current edition of the medical journal Annals of the Rheumatic Diseases, researchers from the U.K. warn that they found links between acetaminophen and heart problems, kidney damage, intestinal problems and an increased risk of death.

Acetaminophen is the most commonly used analgesic painkiller in the world, and is generally believed to be a safe medication. However, in recent years concerns have grown over the risk of liver damage from acetaminophen overdoses, which can result in liver failure and the need for a liver transplant. It has also been liked to dangerous skin reactions, like Stephens-Johnson Syndrome.

The latest study was conducted by researchers from the Leeds Institute of Rheumatic and Musculoskeletal Medicine, who conducted a systematic review of adverse events associated with use of acetaminophen, known as paracetamol in Europe. The researchers looked at eight different studies that contained data on acetaminophen side effects.

Researchers found evidence in the studies of dose-response relationships between heart problems, gastrointestinal injuries and kidney damage. In both cases, the more acetaminophen the patient ingested, the more likely they were to suffer gastrointestinal bleeding or kidney damage. Such correlations are seen as strong evidence of a causal relationship. A dose-response relationship was also seen between acetaminophen use and all-cause mortality.

According to the findings, the more acetaminophen a person took, the more likely they were to have a first heart attack or stroke, the more likely they were to suffer from hypertension, and the more likely they were to suffer upper gastrointestinal hemorrhages.

“Based upon the data presented above, we believe the true risk of paracetamol (acetaminophen) prescription to be higher than that currently perceived in the clinical community,” the researchers concluded. “Given its high usage and availability as an over-the-counter analgesic, a systemic review of paracetamol’s efficacy and tolerability in individual conditions is warranted.”

Tylenol Liver Failure Risks

Acetaminophen is one of the most widely used painkiller medications in the United States, and has been used by millions of Americans. However, Tylenol and acetaminophen have been identified in recent years as a leading cause for liver injury in the United States.

The FDA has indicated that Tylenol and other acetaminophen drugs may be responsible for more than 50,000 emergency room visits each year, including 25,000 hospitalizations and over 450 deaths annually.

In recent years, efforts have been ramped up to bring the risk of acetaminophen overdose to the public’s attention and to reduce the amount of liver injury cases linked to the popular analgesic, which is also found in other pain killers and a number of cold medications.

In 2011, Johnson & Johnson lowered the maximum recommended dosage on Tylenol and other acetaminophen-based products from 4,000 mg per day to 3,000 mg per day. However, studies suggest that there is a narrow margin between the recommended dose and the risk of potentially life-threatening liver failure, with 500mg of acetaminophen contained in each tablet of Extra Strength Tylenol.

A growing number of Tylenol lawsuits are being pursued throughout the United States, alleging that the drug maker has withheld important safety information from the public for decades. In the federal court system, the first Tylenol trial is expected to begin in June 2015, which may provide a gauge for how juries may respond to certain evidence and testimony that is likely to be repeated in dozens of other cases.