Painkillers not only dull physical pain, but they can also dull your emotions.
This is according to a new study that claims acetaminophen (paracetamol) - the main ingredient in the over-the-counter pain reliever Tylenol and paracetamol - has the ability to weaken feelings of happiness and sadness.
Acetaminophen has been in use for more than 70 years, but this is the first time that this side effect has been discovered.
Previous research had shown that acetaminophen works not only on physical pain, but also on psychological pain.
This study takes those results one step further by showing that it also reduces how much users actually feel positive emotions, said Geoffrey Durso, lead author at the Ohio State University.
'This means that using Tylenol or similar products might have broader consequences than previously thought,' Durso said.
'Rather than just being a pain reliever, acetaminophen can be seen as an all-purpose emotion reliever.'
Baldwin Way, an assistant professor of psychology at Ohio State University said people in the study who took the pain reliever didn't appear to know they were reacting differently.
'Most people probably aren't aware of how their emotions may be impacted when they take acetaminophen,' he said.
by Lee Kyung-Ho