More Tylenol Problems? Tylenol Brain Fog?

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Acetaminophen is an over-the-counter and prescription drug used to treat mild pain. In its over-the-counter form, it’s found most commonly in Tylenol and Excedrin. Doctors recommend it for everything from headaches to arthritis pain to cold and flu symptoms to backaches. They even recommend it for babies who get fussy due to spikes in their temperature. Most doctors push acetaminophen like mailmen push junk mail, but while we toss the junk mail, many of us are quick to crack open that bottle of Tylenol and down a couple of pills when we are in pain. I’ve blogged many times on the dangerous side effects of nonsteroidal anti-inflammatory drugs (NSAIDS), such as ibuprofen and naproxen, but there is a growing list of Tylenol problems, and I’ll summarize a few of these in this article. First, let’s explore a new study that gives us yet another reason to not take acetaminophen: it lessens our ability to detect errors.

The Latest Tylenol Brain Fog Study

A recent study published in Social Cognitive and Affective Neuroscience “proposed that the psychological effects of acetaminophen may reflect a widespread blunting of evaluative processing,” meaning that the drug may cause a brain fog.

The study looked at 62 participants, some receiving acetaminophen and some receiving a placebo. Participants underwent go/no-go testing, which measures attention and response. Acetaminophen was shown to lessen the participants’ ability to detect errors during the tests.

So if you are taking acetaminophen, it would be best not to do tasks that require attention and analysis—balancing your checkbook, for example, or proofreading your résumé or operating that rental bulldozer! Or even better, if possible, it would be best not to take acetaminophen at all as there are many other Tylenol problems and side effects.

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Other Acetaminophen Side Effects

The laundry list of Tylenol problems goes on and on, and just when you think the side-effect list can’t get any longer, a new study, such as the recent one above, comes out adding more dirty laundry to the list.

Tylenol Brain Fog for Emotions?

The results of a study I shared last year showed that acetaminophen kind of turns people into emotional zombies when compared against a placebo group. The medicated group and the nonmedicated group had no difference in nonemotional observations, like color saturation, suggesting that acetaminophen has a general blunting effect on emotional processing. This ties right into the study highlighted in this article, showing that acetaminophen did indeed have an effect on the ability to process complex information, leading to a blunted ability to detect errors. Again, more Tylenol brain fog.

Acetaminophen and Deadly Skin Rashes

Acetaminophen and deadly skin rashes? In 2013 the FDA notified consumers about rare and sometimes deadly skin rashes that can result from acetaminophen. I would suspect that most consumers aren’t keenly aware of this potential side effect.

Acetaminophen Can Cause Liver Failure and High Blood Pressure

It has been well established that acetaminophen is also known to cause liver failure in select patients, sometimes even at normal doses. In a recent study, between patients taking Tylenol or Motrin, the participants taking only acetaminophen had more liver enzyme abnormalities. Acetaminophen was also tied to high blood pressure in patients with a cardiovascular risk in this study, which concluded that acetaminophen risks should be evaluated as thoroughly as NSAID risks.

The upshot? Unlike NSAIDs, research has shown that acetaminophen appears to work better with nerves and neurotransmitters, and we’ve noticed that it works much more effectively on nerve pain.  However, acetaminophen blunts more than your nerve pain! It not only lessens your ability to respond emotionally as you typically would, but it also lessens your attention and ability to properly evaluate a process or task, leading to the inability to detect errors. If you must take acetaminophen, at the very least, wait for it to wear off before you do your taxes or make a major life decision. Better yet, try and identify the cause of your pain rather than masking the pain with acetaminophen and risking its side effects.


Chris Centeno, MD is a specialist in regenerative medicine and the new field of Interventional Orthopedics. Centeno pioneered orthopedic stem cell procedures in 2005 and is responsible for a large amount of the published research on stem cell use for orthopedic applications. View Profile

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