This Common Medication May Have An Unexpected Effect On Your Personality

Sometimes we underestimate the effects that over-the-counter (OTC) medications can have on our health and wellness. It's easy to assume that medications that don't require a prescription have fewer side effects than drugs that do require doctor approval. However, this isn't always the case. In fact, some OTC meds can impact not only our physical health but our personality, too. This includes the widely-used drug Tylenol. Containing the active ingredient, acetaminophen, Tylenol operates as an analgesic and fever-reducing drug to relieve mild aches, tooth pain, headache, period cramps, and more (via Tylenol). The medication is believed to accomplish this by raising the body's pain tolerance and helping it to release extra heat.

While rare, Tylenol does come with potential adverse effects, including skin reactions or potential liver damage if a person were to take excessive amounts exceeding more than 4,000 milligrams in one day. The same may occur in the event that a person was to take Tylenol in combination with other acetaminophen-containing drugs or if they simultaneously consumed three or more alcoholic drinks during each day of use. What's not as readily known, however, is that Tylenol may also lower our feelings of empathy for others.

Researchers from a 2016 study published in Social Cognitive and Affective Neuroscience found that the use of acetaminophen may leave us feeling less compassion for the pain of those around us. The study team recruited undergraduate students for a two-part study in which participants received either acetaminophen or a placebo drug. The students read various excerpts describing the physical pain or social pain of a fictional person. Scenarios ranged from getting a cut on one's finger to experiencing the death of a loved one. Students in the second part of the study alternatively witnessed a staged scene of social exclusion or were asked to envision a fellow study participant receiving a loud noise blast. Those in the acetaminophen group reported lower scores of empathetic concern for others.

Similar findings were mirrored in a 2019 study published in Frontiers in Psychology in which researchers gave participants either a placebo or 1,000 milligrams of acetaminophen. Measurements of positive empathy revealed that those who received the analgesic were less emotionally responsive to descriptions of positive events occurring in other people's lives.

In recent years, scientists have taken a closer look at the potential mechanisms behind this connection between acetaminophen and reduced empathy. NPR social science correspondent Shankar Vedantam and National Institutes of Health researcher Dominik Mischkowski tackled the topic on a 2016 episode of the "Hidden Brain” podcast. One theory they highlighted may have to do with our brain's mirror neurons. Offering an example, Mischkowski explained that, normally, the brain region that gets activated when we suffer a burn (physical pain) also lights up when we then see another person get burned (social pain). However, because acetaminophen blunts our feelings of physical pain, it may potentially lessen our feelings of social pain as well. Similarly, in the previously mentioned 2019 study, the researchers stated that acetaminophen suppresses brain activity in the anterior insula and anterior cingulate, two areas that play a role in motivation and emotional awareness. 

However, don't avoid taking Tylenol just because you're afraid you might turn into Ebenezer Scrooge. "[T]he effects of Tylenol on empathy are somewhat modest. We're not talking of a 0 to 100 percent difference here," Vedantam stated as they concluded the podcast episode. "We're talking about maybe a 10 percent difference."