Prompted by concerns over a heightened risk of car crashes, the U.S. Food and Drug Administration (FDA) on Jan. 10 advised makers of Ambien and related sleeping pills to cut recommended doses.
“To decrease the potential risk of impairment with all insomnia drugs, health care professionals should prescribe, and patients should take, the lowest dose capable of treating the patient’s insomnia,” Dr. Ellis Unger, director of drug evaluation at the FDA, says in a statement. “Patients who must drive in the morning or perform some other activity requiring full alertness should talk to their health care professional about whether their sleep medicine is appropriate.”
All of the drugs included in the FDA alert contain zolpidem, a medicine that treats insomnia. The drugs include Ambien, Ambien CR, Edluar and Zolpimist; Ambien and Ambien CR also are available as generics. A zolpidem drug called Intermezzo isn’t included in the alert. Other popular sleeping pills, such as Lunesta and Sonata, also aren’t included, as they don’t contain zolpidem.
The FDA says the zolpidem warning is based on studies showing that for some drivers, zolpidem blood levels the morning after taking the drug can boost the risk of a car crash. The federal agency says zolpidem can impair activities requiring alertness, such as driving.
Unger says the FDA has received “spontaneous” reports (about 700) of driving impairment and auto accidents associated with zolpidem, “but these reports lacked the information necessary to fully understand whether and how zolpidem affected people’s mental alertness and ability to drive. Recently, data from clinical trials and other types of studies have become available, which allowed FDA to better characterize the risk of next-morning impairment.”
Using lower doses of zolpidem at night means less of the drug will remain in the bloodstream in the morning, according to the FDA. Since women eliminate zolpidem from their bodies more slowly than men, the FDA has notified manufacturers that the suggested dose should be reduced for women and that labeling should suggest consideration of a lower dose for men.
The FDA says patients who take extended-release forms of zolpidem face the greatest risk of impairment.
“In this case, the FDA may be behind the eight ball,” Daniel Carlat, an associate clinical professor of psychiatry at Tufts University, told the New York Times. “This has been a known problem. Few doctors will be surprised hearing about this. They’ll say, ‘Oh yeah, we’ve already seen this in our patients.’”
The FDA has told manufacturers that for women, the recommended dose of Ambien and related medication should be decreased from 10 milligrams (mg) to 5 mg for immediate-release drugs (Ambien, Edluar and Zolpimist) and from 12.5 mg to 6.25 mg for extended-release drugs (Ambien CR). For men, the FDA says labels should recommend that health care professionals should weigh prescribing 5 mg for immediate-release drugs and 6.25 mg for extended-release drugs.
In its announcement, the FDA notes: “Drowsiness is listed as a common side effect in the labels of all insomnia drugs, along with warnings that people may still feel drowsy the next day after taking one of these products. Moreover, alertness can be impaired even in people who do not feel drowsy.”
People who take higher doses (10 mg or 12.5 mg) of zolpidem-containing sleeping pills should continue taking the prescribed amounts until they’ve spoken with a health care professional, the FDA says.
The FDA says it’s evaluating the risk of decreased alertness with other insomnia drugs, including over-the-counter versions.
In 2011, about 39 million prescriptions for zolpidem drugs were written in the U.S., according to the FDA. The majority of patients who take these drugs are women.