Acetaminophen, aka Tylenol, has been America's favorite pain reliever for decades. It is one of the safest and most effective products on the market for as long as I can remember. Many of us are aware that this medicine is generally safe to take.
There have been a few problems with this drug and related products over the years...I remember the early 80s when some Tylenol products on store shelves were found to be tainted with a poison and great strides were made to make the product line tamper proof. We found out that there is such a thing as "too much" when it comes to acetaminophen. There were recommendations put in place reduce the risk of liver toxicity.
To this day, acetaminophen products are a large sector of the over-the counter medication market, and many combination products that are RX only contain acetaminophen as well. If that doesn't make a statement, I don't know what does.
Fast forward to 2015. A small study at Ohio State University reveals that this well-known pain reliever may dull a patient's emotional response to positive, upbeat stimulation. In the study,as published in the online journal Psychological Science, approximately 160 college students were involved in one of two experiments leading to this conclusion. In the first study, half of the participants were given a 1000 milligram dose of acetaminophen while the other half were given a placebo. One hour later, all subjects were shown 40 photographs, each with the intention of provoking negative or positive responses. The subjects were asked to rate each photograph as such. Interestingly, the group of subjects in the medication group showed a dulling of both positive and negative emotions during the exercise.
In a follow up study of same design, the two groups were asked how much of the color blue they saw in each image. (The study author's intent here was to see if the medication affected overall judgement as opposed to only emotion.) The result was that the medication vs. no medication had no effect on the color exercise.
The authors conclude by saying that their study leads them to believe that acetaminophen has a "reliable but subtle" effect on emotion. They conclude that there may be more effects on the brain than these, but only future study will determine what those might be. It is also possible that other common medications such as aspirin or ibuprofen may have more effects on us than previously believed.
Sources: WebMd; Wikimedia