Is acetaminophen (Tylenol) safe or is it toxic to the liver? Both answers are true. When acetaminophen (APAP) is taken as directed, it has one of the safest drugs around. However, if too much is taken, it can be toxic.
APAP is the leading cause of acute liver failure in the United States. However, many of those cases are intentional, the result of suicide attempts. More people die from APAP overdose than from overdose by any other over-the-counter (OTC) drug. This is a tricky “fact” because substantially more people die from other over-the-counter drugs, particularly non-steroidal anti-inflammatory drugs (NSAIDs), such as aspirin, ibuprofen (Advil, Motrin, etc), and naproxen (Aleve). Regular use of NSAIDs at normal doses can cause stomach bleeding, kidney problems, and other problems, so when people die from these, the cause of death isn’t directly attributed to NSAID use. Additionally, these complications occur at normal doses, so these deaths are adverse events, and not overdoses.
Data about NSAID deaths are scant. The most recent study is from 1999, reporting 16,500 annual deaths in the U.S. One of the researchers mentioned in an article published by Pro Publica, wrote that the estimates are outdated and “probably one-fourth of that.” Let’s assume that the conservative estimate is 4000 annual deaths. Note though, that the Centers for Disease Control and Prevention (CDC) reported only 15 overdose deaths for the entire class of pain relievers, both prescription and OTC, including ibuprofen in 2010.
In the same year, the CDC recorded 321 APAP deaths, of which more than half were due to accidental overdose. The data also reported 78,000 emergency room visits and 33,000 annual hospitalizations. Compared to 4000 or more NSAID deaths, APAP looks safer, especially considering that 50 million a people use it every week.
So, what is the problem with APAP? This relatively safe drug at recommended doses can be toxic at doses slightly over the recommended ones. Toxicity can occur at just twice the dose of APAP (8000 mgs), where it would take twenty-times a dose of ibuprofen for toxicity to occur. A person with a fever or pain would have to be really out of it to take that much ibuprofen, whereas popping twice the dose of APAP may make sense to someone who doesn’t know the risk.
Although the data vary about the number of APAP deaths, most experts agree that APAP is safe if taken as directed. There were a handful of cases of people who had liver injuries below the maximum dose, and there appears to be no explanation for this.
So how do you take acetaminophen safely?
- Talk to your doctor or nurse about the right dose for you.
- The maximum daily dose for a healthy adult who weighs at least 150 pounds is 4,000 mgs, divided over 24 hours. Liver enzymes elevations have been seen at that dose, albeit rarely. It’s best to take the lowest dose you can, and 3,000 mg per day has a clean safety record for adults. Many liver experts recommend 3000 mgs for their patients who don’t have advanced liver disease.
- Follow dosing instructions precisely. Never take more than 1,000 mgs in a single dose. The January 2014 Harvard Medical School newsletter has an easy-to-read chart listing specific doses.
- Be sure that your total APAP dose includes all sources of this drug. APAP is added to over 600 other medications, including pain meds, sleep meds, cold meds, cough meds, sinus meds, etc. Check here to see if your medication has APAP in it. The latest FDA guidelines recommend that doctors not prescribe combo pills with more than 325 milligrams of acetaminophen.
- Reduce your dose to 2000 mg a day if you are a liver transplant patient or if you drink alcohol. The University of Pennsylvania provides information about safe APAP use for liver transplant patients.
- Start small. A single dose ranges from 325 mg, 500 mg, 650 mg or 1000 mg; some people have good results at the lower doses.
- The risk of liver failure from APAP used for infants and children is greater than for adults, so never let little ones exceed the APAP dose recommended by pediatricians.
Food and Drug Administration: Search “acetaminophen” www.fda.gov.
Get Relief Responsibly (acetaminophen checker)
Harvard Men’s Health Watch, January 2014
University of Pennsylvania Safe Acetaminophen Doses for Liver Transplant Patients
Use Only As Directed by Pro Publica
Use Only As Directed This American Life podcast