Acetaminophen: A Hard Hit on the Liver
Acetaminophen, the same ingredient found in traditional Tylenol, is one of the most widely used painkillers in the United States. It’s inexpensive, easy to find, and less detoxifying than drugs like ibuprofen. However, it’s taxing on the liver.
When you take paracetamol, your liver processes it. During this process, a small amount of a toxic byproduct called NAPQI is produced. Under normal circumstances, the body neutralizes this toxin using an antioxidant called glutathione, preventing further damage.
The problem arises when this system is pushed too far, especially with repeated use, high doses, or mixing with alcohol, leaving the liver vulnerable.
But if you:
If you take too much acetaminophen in a day,
use it regularly over time, or
have low glutathione levels (which can occur if you drink alcohol frequently, are malnourished, or have certain health conditions)
, your liver may not be able to keep up. That toxic byproduct, NAPQI, begins to build up. It binds to liver cells, damaging them and, in severe cases, triggering liver failure.
Dr. Melillo says 4,000 milligrams of acetaminophen per day is the maximum safe dose for most adults. That’s about eight Tylenol PM tablets in 24 hours. It’s surprisingly easy to exceed this threshold, especially since acetaminophen is hidden in many other over-the-counter cold, flu, or nasal congestion medications.
Why so many Americans face hidden risks?
Experts estimate that approximately one in three Americans suffers from some form of liver disease, or more than 100 million people in total. Many of them may unknowingly be putting their livers under additional stress by taking medications they think are safe on a daily basis.
The concern became so serious that the U.S. Food and Drug Administration (FDA) took action in 2011. Regulators urged pharmaceutical companies to limit the amount of acetaminophen in combination medications, such as Tylenol PM, to 325 milligrams per tablet.
The reason was clear: research had shown that higher doses offered little pain relief but significantly increased the risk of liver damage.
Despite this, Tylenol PM still provides 500 milligrams of acetaminophen per pill.
