Tylenol may seem like a pretty damn vanilla drug. Soccer moms carry the painkiller around in their purses. You can buy it in bulk at Costco. But recently, a series of reports have begun to reveal a darker side to the medication, also known by its generic name of acetaminophen: Word is finally spreading that the little white pills have the potential to cause fatal liver damage when taken in higher doses than directed. And perhaps most unnerving, several studies have suggested that it may cause emotional side effects, too.
Last month, Tylenol’s psychological effects became the focus of a New York Times Modern Love column, whose headline asked: Can Tylenol help heal a broken heart? In the piece, about a devastating college romance, writer Melissa Hill brought research on the subject to a broad audience, explaining: “Scientists found that acetaminophen can reduce physical and neural responses associated with the pain of social rejection, whether in romantic relationships, friendships or otherwise. So if you’re hurting from heartache, try popping some Tylenol.”
But should we really start taking Tylenol as a makeshift anti-anxiety drug?
I posed this question to the psychologists spearheading the research into its effects on our emotions, and the short answer is: definitely not. If anything, our conversations even left me feeling a bit spooked about the times I’ve taken it to cure minor maladies like headaches that might’ve resolved on their own. Because here’s the thing: Along with appearing to blunt physical and emotional pain, acetaminophen also appears to numb joy and empathy.
So how did psychologists discover these apparent neurological side effects in the first place?
Dan Randles is a social psychologist from the University of Toronto and one of a handful of researchers studying Tylenol's effects on our emotions. "The work we’ve done so far does imply that Tylenol could actually be having a tranquilizing effect when taking it daily," he told me.
Randles reached this conclusion, in part, from an study he conducted back in 2013 that built off previous research from Nathan DeWall, who runs the Social Psychology lab at the University of Kentucky and was the first to discover that Tylenol could dull the pain of emotional rejection. Randles wanted to find out how else acetaminophen could affect emotional responses.
For his experiment, participants were placed in a stressful, anxiety-inducing situation—such as writing about their own death or watching a creepy David Lynch clip—and then asked to make hypothetical moral decisions. Lo and behold, Randles found that participants who were given acetaminophen beforehand were much less likely to be affected by stress and anxiety in their decision-making than participants who took a placebo.
"People who took acetaminophen didn't exhibit the same type of distress. It dulled their reaction to it," Randles said. "Our interpretation of acetaminophen therefore was just—they weren’t as emotionally bothered."
Baldwin Way, a psychologist at Ohio State University, has also observed the drug’s emotional blunting—and the notion that it may be a double-edged sword.
In a 2015 study, Way and a team of researchers found that when people took acetaminophen and looked at gruesome photos of things like mutilated bodies, they weren't as bothered as those who took a placebo, based on self reports. However, when participants on acetaminophen looked at happy photos—pictures of puppies or a child smiling—they didn't feel as much joy as the participants on placebo, either.
"Tylenol reduced the positive and the negative [reactions] by about 10% to 20%," Way told me of the research, which was published in the journal Psychological Science. While the findings, which were based on how the participants rated the photos, are still preliminary, he’s confident they’re accurate. "Tylenol is blunting emotion," he said. "That finding will stick."
So the research has shown that Tylenol appears to numb stress and joy. But perhaps most alarming, it also appears to blunt empathy.
In another one of Way’s experiments, published this year in the journal Social Cognitive and Affective Neuroscience, participants were asked to read vignettes about a person who was suffering in some way—from a painful injury, for example, or the death of parent. Sure enough, when participants took acetaminophen beforehand, they were more likely to rate the person’s pain as less severe than those who took a placebo.
"Empathy is important,” Way emphasized in a previous report about his findings. “If you are having an argument with your spouse and you just took acetaminophen, this research suggests you might be less understanding of what you did to hurt your spouse's feelings.”
On the flip side, depending on the context, it’s possible this finding could be used to a person’s advantage, said Way. For example, curbing empathy could theoretically be beneficial for a surgeon cutting people open, he said, but not for a doctor treating and diagnosing a patient. But either way, you should know what you’re swallowing beforehand.
The scary reality is that scientists still aren’t sure what exactly happens to your brain once you swallow a Tylenol caplet—and there's no way to pick and choose how it will affect us or to what degree. So taking it for any singular condition, from a headache to, say, anxiety before a big presentation, could be something of a game of psychological roulette.
"A drug like acetaminophen doesn't work in these isolated ways," Randles said. "I think it’s probably fair to assume that any medication that affects mental processes has multiple effects. And once a drug crosses the barrier into your nervous system, there's a limitation to how effectively we can study it."
Research using MRI brain scans suggests that physical pain and emotional pain are processed in overlapping areas of the brain, so scientists theorize that if acetaminophen can target physical pain, it can also target emotional pain. But the experts I spoke to believe other over-the-counter painkillers such as NSAIDs (which count Advil and Aleve among them) don't have the same emotional blunting effects—or if they do, it’s to a much lesser degree. So why acetaminophen?
"We don't know how Tylenol does it," said Way. "I wish I had a good answer."
He added that this is the case for many drugs used to treat psychological conditions. "Even the psychiatric drugs aren’t tested for everyday social behavior," he explained. "How does Prozac really act? Nobody knows. I think with these substances we don't know the full extent of what we’re doing."
But here's where the real problem lies: An antidepressant such as Prozac is prescribed by a doctor. Like most antidepressants, it can come with pretty heavy side effects—but patients can weigh the pros and cons of taking it with their physician before popping the first pill.
With Tylenol, however, and the hundreds of other over-the-counter medications that include acetaminophen as a major ingredient, anyone can buy it—no doctor consult necessary—despite the fact that even a relatively small overdose can potentially damage the liver. From 2001 to 2010, more than 1,500 people died from accidental acetaminophen poisoning in this country. And annually, acetaminophen overdoses send about 78,000 Americans to the emergency room, leading to roughly 33,000 hospitalizations, according to a scathing 2013 ProPublica investigation of McNeil Consumer Healthcare, the company that makes Tylenol.
So along with its unpredictable emotional effects, Tylenol, taken every day, could bring serious physical consequences, too. "I hope people don't take away the message that acetaminophen is an alternative to anti-anxiety medications,” said Randles. “We have a wide range of anti-anxiety medications that are probably safer."
And what does Tylenol think of all this? When I reached out to McNeil for comment, a spokesperson did not directly address the research on the drug's apparent impact on our emotions, instead noting, "In general, I can tell you that, as the makers of TYLENOL, our priority is to provide consumers with safe, effective and high-quality products. We want to help people stay healthy and help take care of them when they are sick."
So there you have it. While Tylenol might temporarily relieve your broken heart, as the Modern Love column suggests, it might also take away your joy, reduce your empathy, and turn you and your liver into a zombie. We won’t likely see therapists prescribing it anytime soon.
Taryn Hillin is Fusion's love and sex writer, with a large focus on the science of relationships. She also loves dogs, Bourbon barrel-aged beers and popcorn — not necessarily in that order.