Many over-the-counter medicines marketed for treating colds and flu contain acetaminophen (paracetamol in Europe, Australia and New Zealand). This non-aspirin pain reliever helps lower fever. Acetaminophen (APAP) is the active ingredient in Tylenol. Many people think it is extremely safe, and that may be why they take too much when they are sick with a bad cold or the flu. Even people taking APAP for pain can overdose if they are not careful.
Research Shows People Overdosing on Acetaminophen:
A study suggests that people taking cold remedies are more likely to inadvertently take more than the recommended dose (British Journal of Clinical Pharmacology, March 25, 2018). Large doses of acetaminophen can lead to kidney or liver damage.
The authors of this research note:
“Paracetamol [acetaminophen] is an active ingredient present in hundreds of over‐the‐counter (OTC) and prescription (Rx) medications indicated for pain and fever as well as in many multi‐ingredient OTC medications additionally indicated for symptoms associated with colds, flu, allergies and sleeplessness. It is considered safe when dosed as directed, but, in overdose, has been associated with liver injury, and with calls to poison control centres (estimated around 112 000 year), emergency room visits (59 000/year) and hospitalizations (38 000/year).”
The authors note that about one third of the people overdosing on acetaminophen do so unintentionally. That’s in part due to the fact that many people don’t bother to read the labels of their OTC medications. They don’t realize how easy it is to exceed the recommended dose.
How Many People Were Overdosing on Acetaminophen?
The investigators reported that 6.3% of the people taking APAP in OTC medications “exceeded the maximum daily dose on at least one day.” It happened more frequently during cold and flu season. That’s in part because there are now so many multi-symptom treatments on the market containing acetaminophen.
Does APAP Even Help Against Flu?
A study in the journal Respirology (online, Dec. 6, 2015) raises doubt that acetaminophen is even helpful against the flu. New Zealand investigators gave 80 people either placebo or acetaminophen to ease their flu-like symptoms. They were tracked for five days.
Patients kept detailed records of their temperature and recorded their symptoms. The researchers analyzed viral shedding during the experiment. There was no obvious difference between the people taking placebo and those taking acetaminophen.
In another study, Australian and New Zealand clinicians randomly assigned 700 hospitalized children in the ICU to receive either placebo or acetaminophen. They wanted to know if lowering a fever with APAP would improve recovery. You guessed it, there was no difference between the two groups (New England Journal of Medicine, Dec. 3, 2015).
Overdosing on Acetaminophen:
Many people believe that acetaminophen is the safest pain reliever in the pharmacy. They have heard about the dangers of NSAIDs like ibuprofen and naproxen. For decades, acetaminophen has been promoted as a safer alternative .
When taken in recommended doses APAP is generally well tolerated. But overdosing on acetaminophen is not as difficult as many people may assume.
A reader recently wondered if her doctor’s recommendation about a safe dose of acetaminophen is true:
Q. I have severe pain in my legs, with no diagnosed cause. The pain is worse when I am standing than if I sit or lie down. Walking or biking relieves it. I have also gotten some relief from physical therapy and therapeutic massage.
When the pain is bad, 4,000 mg of acetaminophen taken over 24 hours reduces it to a level that doesn’t interfere with my daily routine.
My primary care physician says that taking 4,000 mg of acetaminophen a day for extended periods of time will not hurt me. However, he has made past errors in prescribing medication, so I’d like another opinion. I seldom drink alcohol but am concerned about hepatotoxicity.
I am otherwise very healthy and lead an active life. I have no pain anywhere else, and no diabetes, cancer or other conditions. I do not smoke or take recreational drugs or other prescription medications such as statins that have been implicated in muscle pain. What can you tell me about the safety of chronic acetaminophen use?
A. The maximum daily dose of acetaminophen (Tylenol) is surprisingly controversial. The manufacturer of Tylenol suggests a maximum dose of “Tylenol Regular Strength Tablets (325 mg each)” at 3,250 mg a day.
The company suggests that if someone is taking Tylenol Extra Strength Tablets (500 mg each), the daily dose should be no more than 3,000 mg a day. The company offers an exception for health care professionals to “exercise their discretion and recommend up to 4000 mg/day.”
While that may be appropriate for a limited time period, we suspect that chronic use of acetaminophen should remain below that maximum level. You might ask your doctor to test your liver enzymes periodically. If they show any signs of rising, ask your doctor about the dietary supplement NAC (N-acetylcysteine). This compound can help protect the liver by boosting levels of glutathione. This antioxidant helps detoxify APAP.
To learn more about acetaminophen toxicity you may wish to read this article:
It Acetaminophen Is Killing People, Why Should You Trust Tylenol?
People’s Pharmacy Perspective:
No matter how sick you feel when you have the flu, be sure to read and follow the instructions carefully so as not to end up overdosing on acetaminophen.
Do you read OTC labels? Ever run into problems? Share your story below in the comment section.
