Pain is Pain!

 

Over-the-Counter Relief From Pains and Pleasures Alike

Acetaminophen Blunts Evaluation Sensitivity to Both Negative and Positive Stimuli

1. Geoffrey R. O. Durso1
2. Andrew Luttrell1
3. Baldwin M. Way1,2

1. ¹Department of Psychology, The Ohio State University
2. ²Institute for Behavioral Medicine Research, The Ohio State University Medical Center

1. Geoffrey R. O. Durso, The Ohio State University, Department of Psychology, 1827 Neil Ave., Columbus, OH 43210 E-mail: durso.9@osu.edu
2. Baldwin M. Way, The Ohio State University, Department of Psychology, 1827 Neil Ave., Columbus, OH 43210 E-mail: way.37@osu.edu

1. Author Contributions G. R. O. Durso developed the study concept. All authors contributed to the study design. Data were collected and analyzed by G. R. O. Durso and A. Luttrell. G. R. O. Durso drafted the manuscript, and A. Luttrell and B. M. Way provided critical revisions. All authors approved the final version of the manuscript for submission.

Abstract

Acetaminophen, an effective and popular over-the-counter pain reliever (e.g., the active ingredient in Tylenol), has recently been shown to blunt individuals’ reactivity to a range of negative stimuli in addition to physical pain. Because accumulating research has shown that individuals’ reactivity to both negative and positive stimuli can be influenced by a single factor (an idea known as differential susceptibility), we conducted two experiments testing whether acetaminophen blunted individuals’ evaluations of and emotional reactions to both negative and positive images from the International Affective Picture System. Participants who took acetaminophen evaluated unpleasant stimuli less negatively and pleasant stimuli less positively, compared with participants who took a placebo. Participants in the acetaminophen condition also rated both negative and positive stimuli as less emotionally arousing than did participants in the placebo condition (Studies 1 and 2), whereas nonevaluative ratings (extent of color saturation in each image; Study 2) were not affected by drug condition. These findings suggest that acetaminophen has a general blunting effect on individuals’ evaluative and emotional processing, irrespective of negative or positive valence.