Acetaminophen Overdose: Are You at Risk?

Acetaminophen, the medication commonly used to relieve a headache, soothe a sore throat, relax abdominal cramps, and bring down a fever, can also damage your liver if you take too much. But since the maximum recommended daily limit is a whopping 4,000 mg, it’s hard to believe anyone could easily overdose. Yet more than 78,000 people end up in the emergency room in each year due to just this.

That may be due to the fact that there are more than 600 over-the-counter and prescription medications that contain acetaminophen, including painkillers such as Tylenol®, Midol PMS®, Percocet®, and Vicodin®, as well as cold and flu remedies such as Dayquil® and Phenflu®. So overdosing is easier than it sounds, especially if you are taking more than one of these medications at the same time. That’s why some health experts are calling for a closer look at the use of acetaminophen and, in some cases, recommending a lower daily limit.

Acetaminophen Use and Liver Damage

At normal therapeutic doses, acetaminophen is considered safe for most people, yet acetaminophen overdose has become a leading cause of acute liver failure in the US. The risk of severe liver damage, leading to the need for a transplant or even death, increases if you take more than the recommended amount of acetaminophen in a 24-hour period, take more than one acetaminophen-containing product at a time, or drink alcohol while taking acetaminophen.

Jean Burg, MD, family physician, Albert Einstein College of Medicine Assistant Professor and Chair of the Department of Family & Social Medicine at Jacobi Medical Center in New York City, points out that even at normal doses, acetaminophen can cause liver damage when taken along with certain other medications. These include:

  • Some anticonvulsants (such as carbamazepine and phenobarbital)
  • Trimethoprim-sulfamethoxazole (a commonly used antibiotic, known as Bactrim)
  • Several herbal supplements, including echinacea, kava, willow, and meadowsweet

Acetaminophen Use and Pregnancy

Acetaminophen has long been considered safe for use during pregnancy and is, in fact, the most commonly used painkiller among pregnant women. Recently, however, a UCLA study found that the babies of mothers who used acetaminophen during pregnancy were at significantly higher risk of being diagnosed with hyperkinetic or ADHD-like behaviors in early childhood than babies of mothers who didn’t use acetaminophen. The longer the mothers took acetaminophen, especially if they used the painkiller into their second and third trimesters, the higher the risk. While more studies are necessary before a cause-and-effect relationship can be confirmed, the research suggests that acetaminophen disrupts normal hormone regulation, causing exposure to abnormal levels of hormones and possibly influencing fetal brain development.

Reduce Your Risk of Acetaminophen Overdose

To protect yourself from acetaminophen overdose, Burg suggests the following guidelines:

  1. When you are prescribed any new medication, be sure to check with your pharmacist or doctor to see whether it is OK to take acetaminophen at the same time.
  2. Check all labels on over-the-counter medications, especially painkillers and cold and flu remedies, to see if they contain acetaminophen. If you regularly use more than one of these medications, consider an alternative.
  3. Don’t take more than the recommended or prescribed dosage.
  4. Avoid taking more than one acetaminophen-containing medication at the same time.
  5. Check to be sure the product you use contains no more than 325 mg of acetaminophen per tablet, capsule or dose unit, unless otherwise prescribed by your doctor.
  6. Avoid taking acetaminophen if you drink three or more alcoholic beverages a day.

The bottom line: Limit the amount of acetaminophen you take to recommended doses. If you are taking more than one medication, if you have liver disease or a history of liver problems, or if you’re pregnant, discuss your drug and supplement regimen with your physician or pharmacist before you use a product that contains acetaminophen. It may be wise to use an alternative product, and a health care professional who is familiar with these types of medications can help you make a better choice.

Jean Burg, MD, reviewed this article.



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