Tylenol (Acetaminophen) Liver Damage
Dennis Lee, MD
Dr. Lee was born in Shanghai, China, and received his college and medical training in the United States. He is fluent in English and three Chinese dialects. He graduated with chemistry departmental honors from Harvey Mudd College. He was appointed president of AOA society at UCLA School of Medicine. He underwent internal medicine residency and gastroenterology fellowship training at Cedars Sinai Medical Center.
- "Is it safe for me to take Tylenol?"
- Do the recommended doses of Tylenol cause any liver damage?
- Why should we know that the generic name of Tylenol is acetaminophen?
- Just how much acetaminophen is safe to take?
- How is acetaminophen processed (metabolized) in the body?
- How does an overdose of acetaminophen cause liver injury?
- Is overdose with acetaminophen usually accidental or intentional?
- How can accidental overdose be avoided in adults?
- How can overdose be avoided in children?
- What are the symptoms and signs of acetaminophen-induced liver damage?
- What should be done if acetaminophen toxicity is suspected?
- Acetaminophen (Tylenol) Liver Damage At A Glance
- Patient Comments: Tylenol Liver Damage - Symptoms
"Is it safe for me to take Tylenol?"
Tylenol is currently the most popular painkiller in the United States. Americans take over 8 billion pills (tablets or capsules) of Tylenol each year. Acetaminophen is the general (generic) name for Tylenol, which is a brand name. Although acetaminophen is contained in over 200 medications, most of them do not have the name "Tylenol" on their labels. Moreover, just about every patient with liver disease in my practice invariably asks:
- "Is it safe for me to take Tylenol?" or
- "How much Tylenol can I take?"
These questions highlight the public's awareness of the potential for acetaminophen to cause liver damage or injury.
Tylenol is a very effective pain-killing (analgesic) and fever-reducing (anti-pyretic) agent. It is also a very safe drug as long as the recommended dosage is not exceeded. In fact, the use of Tylenol instead of aspirin to treat fevers in infants has greatly reduced the occurrence of Reye's syndrome, an often fatal form of liver failure. Ironically, however, taking too much Tylenol (an overdose) can also cause liver failure, although by a different process (mechanism), as discussed below.
Do the recommended doses of Tylenol cause any liver damage?
Some early reports did describe the occurrence of chronic liver disease that was associated with the long-term use of Tylenol in recommended doses. These studies were published in the 1970's, however, and I suspect that many of these patients may have had unrecognized chronic hepatitis C infection. Anyway, today, the consensus is that the usual doses of Tylenol cause significant liver damage only rarely, or not at all in people with normal livers.
Likewise, a person with liver disease does not appear to be at an increased risk of developing additional liver injury from taking Tylenol. This is so-regardless of the cause of the liver disease and provided the patient does not drink alcohol regularly. Thus, Tylenol is quite safe to use in the recommended doses in patients with acute (brief duration) or chronic (long duration) hepatitis. For example, Tylenol is routinely prescribed to treat the flu-like symptoms that can be caused by interferon treatment for patients with chronic hepatitis. Keep in mind, however, that all drugs, including Tylenol, should be used with caution, if at all, in patients with severe liver disease, such as advanced cirrhosis (scarring of the liver) or liver failure.
Even though Tylenol most likely does not cause serious liver damage in recommended doses, it can cause elevations of liver enzymes in the blood suggesting injury to the liver. In a study of 145 healthy subjects who were randomized to receive placebo or 4 grams of Tylenol daily for two weeks, subjects in the placebo group experienced no elevations of ALT, a liver enzyme, but 33%-44% of the subjects in the Tylenol group had ALT elevations greater than three times the upper limits of normal. The highest ALT elevation was greater than 500 which is approximately 10 times the upper limit of normal. All enzyme elevations returned to normal after stopping Tylenol. Thus, recommended doses of Tylenol given to healthy subjects for two weeks can cause mild to moderate reversible liver injury. Tylenol, like all other medications should be used cautiously under a doctor's supervision with monitoring of liver enzyme levels.
Viewers share their comments
- Submit »
- Submit »
Find out what women really need.