In the ads for the new sleep drug Lunesta, a pale green luna moth – they’re nocturnal – floats peacefully across the TV or computer screen, hoping to lure you into asking your doctor to prescribe the medication.

What the $60 million ad campaign doesn’t mention is that there’s little research showing Lunesta works any better than prescription sleep aids already on the market. Also, sleep experts say there are drug-free ways to get a good night’s sleep.

Insomnia plagues an estimated 70 million Americans, according to the National Institutes of Health, and many of them seek prescriptions as a quick route to a good night’s sleep.

“I try to encourage people not to use these medicines because of side effects,” said Dr. Glenn Singer, who leads the sleep disorders center at Broward General Medical Center in Fort Lauderdale, Fla. Singer said some people become dependent on the medications.

“We don’t call it addiction, we call it habituation,” he said. “We want people to learn how to sleep better, and there are other ways of doing that.”

Despite such advice, the appeal of sleep medications remains strong.

Sales of Lunesta, launched in early 2005, have been brisk. Ambien and its latest version, Ambien CR, are big sellers, too, along with Sonata and other prescription sleep medications.

The medications, in a class called “sedative/hypnotics,” work by enhancing brain chemicals that allow the mind to calm and for drowsiness to occur.

People 65 and older are most likely to get sleeping pill prescriptions, Medco found, based on an analysis of prescription drug claims of 2.4 million Americans between 2000 and 2004. But use of the pills in adults 20 to 44 doubled during that four-year span, the study showed.

Consumer advocates say Lunesta and Ambien are the latest in a series of medications that have been marketed directly to consumers since federal law was relaxed to allow such sales tactics by pharmaceutical manufacturers in 1997.

While doctors say there are circumstances in which people can benefit from taking a sleeping pill, many causes of insomnia are tied to lifestyle choices: drinking caffeinated beverages with dinner or later, eating chocolate or exercising right before bed.

Insomnia takes a few forms – difficulty falling asleep, or falling asleep but waking early and then not being able to go back to sleep, or waking frequently, said Dr. Laurence Smolley, medical director of the sleep disorders center at Cleveland Clinic Florida in Weston.

People who wake frequently in the night may need to be studied to determine whether they have sleep apnea, a condition in which the throat closes and the person stops breathing and wakes gasping for breath, or another condition called periodic limb movement, in which the legs or arms move involuntarily, sometimes jerking the person awake.