Reports in the media of bizarre behaviors -including eating, driving and even shop occurred during Ambien induced sleep have raised concerns among the millions of Americans who take the popular prescription sleep aid. But according to most experts, there is no need to Panic.
The Numbers
"It may seem like there's an explosion of these cases, but when you've got 26 million prescriptions written and just 48 cases reported to the US Food and Drug Administration [FDA]-most of which involved inappropriate use of the medication-the numbers are extremely small," says Donna Arand, clinical director of the Kettering Sleep Disorders Center in Dayton, Ohio, and a spokeswoman for the American Academy of Sleep Medicine (AASM).
These figures are from the FDAs adverse events reporting da tabase, which has tracked patient reports of medication-associated sleepwalking since 1997.Based on those numbers, Arand says she believes, "Overall, the medications that are available are safe for almost everyone."
Michael H. Silber, codirector of the Mayo Clinic's Sleep Disorders Center, and president of the AASM, who has studied the phenomenon of Ambien-linked binge sleep-eating, says, "There's little doubt in my mind or those of my colleagues that Ambien can do this. I don't think it's common; I think it's a very small minority of patients who use Ambien who do this."
In sleep-eating, individuals gain weight after repeated bingeing at night, with no recollection of it when they awake. "We've had patients who, as soon as they started using Ambien, started sleep-eating," Silber says. "Then they stopped Ambien, and the sleep-eating went away. We first published on this a few years ago, and in the five years since, we have not seen it with other sleep medications."
Explanation
According to Dr. Michael Thorpy, director of the Sleep-\Wake Disorders Center at Montefiore Medical Center in New York City, specialists have long known that the risk of sleepwalking and other parasomnias rise when people take a sleeping pill.
Sleepwalking occurs when the brain doesn't catch up with the body as it emerges into wakefulness. "These parasomnias are related to the amount of time people have been in fairly deep, slow-wave sleep," Thorpy says. "So, if a sleep agent makes you sleep more consistently, with less arousals, you're more likely to have more of these behaviors."
Sanofi-Aventis, the French company that manufactures Ambien, says that it is aware that parasomnias are associated with this medication. In fact, Ambien's package insert states that parasomnias are a rare but potential side effect, as is temporary memory loss.
According to Arand and Thorpy, there's no hard evidence that Ambien users are more likely to experience parasomnias than people who use other sleep aids. Ambien, approved in 1993-and its two newer rivals in the billion-dollar sleep-aid market, Sonata (approved in2002) and Lunesta (approved in 2005)-all work in much the same way.
"Maybe there is something specific that makes Ambien more likely to produce this type of behavior than other hypnotics, but that's hard to say at this point, because it's, by far the largest medication used out there," Thorpy says.
Experts speculate that the reason these parasomnias are seen in Ambien users is related to the drug's half-life, or the amount of time the drug stays active in the brain. "It lingers [for] a shorter time than Lunesta and a longer time than Sonata," Silber says. "So, it may have something to do with that half-life-the fact that it stays around for three to five hours may be just the length that's needed to do what it does. But we're not entirely sure."
Take As Directed
One thing that experts are sure of is that Ambien, like all drugs, must be taken as directed. in many of the reported cases, users had combined Ambien with alcohol or other drugs, or had taken it too soon before a hazardous activity, such as driving. "People may also be exceeding the [recommended] dose," Thorpy says. "The usual dose is 5 or 10 milligrams [mg], but sometimes people will take 20 mg. That could be a factor."
The AASM recommends that consumers read the fine print on the package inserts that come with all prescription sleep medications, to familiarize themselves with the proper usage and any potential side effects.
Silber says he still routinely prescribes Ambien to his patients, but added there's a real need for awareness-not panic-about the drug. "I'm hoping people will learn that if they are prescribed Ambien, [they should] be aware that there are potential side effects-as there are with any drug. And [they should] be prepared to stop using it if these side effects develop."
According to Sanofi-Aventis, the most common side effects of Ambien include daytime drowsiness, dizziness and coordination difficulties. Many of these side effects can be avoided by taking the proper dose and avoiding alcohol.
