The drugs in question are Tylenol PM, Excedrin PM and other widely used acetaminophen pain drugs that include a sleep aid.
US health regulators have told the drug makers that the so called "sleep aids" failed to show any significant benefit in a key study.
This comes 15-years after the drug makers submitted the data. Their review found that patients taking the drugs did not fall asleep significantly faster than those who took only acetaminophen or the sedative known as diphenhydramine citrate.
This news comes amid closer scrutiny of dozens of other Tylenol products for children that were recalled last Friday.
It's still not clear what kind of impact the agency's decision could have on the products.
