Acetaminophen, the active ingredient in the popular pain reliever Tylenol, is no more effective than a placebo (fake Tylenol) for reducing joint pain. A meta-analysis that combined the results of 13 randomized studies found that the drug was clinically insignificant for reducing pain in people with low back pain and arthritis of the hip or knee. Acetaminophen is the number one cause of poisoning in the United States. Users are four times more likely to experience abnormal liver function tests. The study showed that the drug’s effect on pain is minimal or nonexistent, and that the risks of taking the drug greatly exceed any benefits.
Source: British Medical Journal, 350: H1225, 2015