About 8 million Americans take prescription sleeping pills.
Now the Food and Drug Administration says more warning needs to be added to the pills
The FDA says the sleeping pill Lunesta must alert users to the possibility of being too drowsy to drive or perform other activities even after they wake up the next morning.
The dosage of Lunesta will also be lowered.
A recent study showed that even when patients felt alert the next day, their coordination and driving skills were likely to be impaired.