The U.S. Food and Drug Administration has announced it required the manufacturer of the sleep drug Lunesta (eszopiclone) to change the drug label and lower the current recommended starting dose. Data show that eszopiclone levels in some patients may be high enough the morning after use to impair activities that require alertness, including driving, even if they feel fully awake.

Taken at bedtime, the recommended starting dose of Lunesta (eszopiclone) has been decreased from 2 milligrams to 1 mg for both men and women. The 1 mg dose can be increased to 2 mg or 3 mg if needed, but the higher doses are more likely to result in next-day impairment of driving and other activities that require full alertness. Using lower doses means less drug will remain in the body in the morning hours.

Patients currently taking the 2 mg and 3 mg doses of Lunesta should contact their health care professional to ask for instructions on how to continue to take their medicine safely at a dose that is best for them.

"To help ensure patient safety, health care professionals should prescribe, and patients should take, the lowest dose of a sleep medicine that effectively treats their insomnia," said Ellis Unger, M.D., director, Office of Drug Evaluation I in the FDA's Center for Drug Evaluation and Research. "Recently, data from clinical trials and other types of studies have become available, which allowed the FDA to better characterize the risk of next-morning impairment with sleep drugs."

The dose change is based, in part, on findings from a study of 91 healthy adults ages 25 to 40. The study shows, compared to an inactive pill (placebo), Lunesta 3 mg was associated with severe next-morning psychomotor and memory impairment in both men and women 7.5 hours after taking the drug. The study found that recommended doses can cause impairment to driving skills, memory, and coordination as long as 11 hours after the drug is taken. Despite these long-lasting effects, patients were often unaware they were impaired.

The FDA today approved changes to the Lunesta prescribing information (label) and the patient Medication Guide to include these new prescribing recommendations. The drug labels for generic eszopiclone products must also be updated to include these changes. In a drug safety communication issued today, the FDA urges health care professionals to caution patients taking Lunesta about the risk of next-morning impairment for activities that require mental alertness, including driving. Alertness can be impaired even in people who do not feel drowsy.

Drowsiness is listed as a common side effect for all insomnia drugs, along with warnings that people may still feel drowsy the next day after taking one of these products. The FDA is continuing to evaluate the risk of impaired mental alertness with the entire class of sleep drugs, including over-the-counter drugs, and will update the public as new information becomes available.

In Jan. 2013, the FDA announced a dose reduction for sleep drugs that contain the active ingredient zolpidem, such as Ambien and Ambien CR, because of the risk of next morning impairment.

Health care professionals and the public can report side effects from the use of medicines to FDA's MedWatch program.