Common painkillers like Tylenol, Advil or Aleve are typically used to treat physical pain in the body such as headaches, cramps or aches, but new studies show these painkillers may have an effect on emotional pain as well. However, it is also believed that specifically acetaminophen (Tylenol) may also affect feelings of happiness.
Previous studies have supported that Tylenol can ease the pain of rejection, the pain caused by teasing or feelings of existential dread. Another study suggested the drug could decrease anxiety. The previous studies found that the neurons that fire in response to emotional pain are the same neurons that fire in response to physical pain. The new studies also reveal acetaminophen dulls feelings of pleasure.
One recent study entitled “Over-the-Counter Relief From Pains and Pleasures Alike: Acetaminophen Blunts Evaluation Sensitivity to Both Negative and Positive Stimuli” was conducted at Ohio State University where 82 college students looked at 40 pictures meant to evoke an emotional response. Half of the students took acetaminophen and the other half took a placebo pill. The participants rated the photos on a scale from positive to negative emotional responses both before and after taking the drug. The pictures viewed were sad (crying children), joyful (children and cats) and emotionally neutral (a cow in a field). The study, published in Psychological Science, found that the acetaminophen-treated group viewed the photos as more neutral than the placebo group. They rated each photo less extremely than those who had taken the placebo. Those who had taken acetaminophen reported an average emotional response of 5.85, while those who had taken the placebo reported a response of 6.76.
The exact biological reasoning for this phenomenon was not explored in this study, but researchers propose that it may be due to anything from the acetaminophen’s properties that change in serotonin neurotransmission in the brain, reduce inflammatory signaling in the brain or decrease activation in the brain areas responsible for emotion. They hope further research will better explain this sensation.