Americans'' 24-hour lifestyle and job demands — particularly shift work — contribute to sleeping problems.

Just ask Dr. Michael Mullins, who works the graveyard shift one night a week at a local hospital. To make sure he gets adequate rest, both mentally and physically, and to remain alert and sharp on the job, he adjusts his sleep cycle when he needs to. With the help of Ambien — which he takes in the afternoon prior to his night shift — Mullins is able to sleep through the afternoon and early evening and wake up well rested for his 11 p.m. shift.

"I sleep for awhile and I get up and I''m fine. I remain alert and am able to work the night shift," said Mullins, an associate professor of emergency medicine and medical toxicologist at Washington University School of Medicine at Barnes Jewish Hospital and St. Louis Children''s Hospital.

An estimated 20 million Americans report that they suffer from occasional or chronic insomnia, Mullins said.

One way people are battling back and coping with the loss of sleep is by using Ambien. Mullins describes Ambien "as a hypnotic agent — a medicine that induces sleep," he said.

"Insomnia is a major health problem in the U.S.," said Frank Steinberg, a medical consultant for Sanofi-aventis, the maker of Ambien. It can be associated with medical and psychiatric disorders. Not to mention that lack of sleep can effect one''s family, social life and work productivity.

Dr. Damon Broyles, a family medicine specialist at St. Anthony''s Medical Center who also has a private practice at Fenton Family Medicine, 714 Gravois Road, sees patients who have insomnia because of anxiety and depression, as well as those that develop the condition for no reason at all.

Insomnia can occur for just one night or last for years. Some people never seek out a doctor for help while others experience severe problems and visit the doctor''s office for prescription sleep medication.

The most popular sleep prescription drug is Ambien, which has received some negative media attention recently for allegedly bizarre side effects, such as sleepwalking, raiding the refrigerator while asleep and even driving while asleep.

In the U.S., about 4 percent of the general population has experienced sleepwalking.

"Based on all the clinical studies we have conducted with Ambien and reports received to date, we believe the incidence of the somnambulism (sleepwalking) is rare," Steinberg said. "I think one has to look with caution at these anecdotal reports."

"I think that it''s a limited patient population that is having very bizarre behavior — amnesia and doing things they don''t remember," Broyles said.

Mullins believes the bizarre behavior publicized in the media is linked to misuse of the drug. It is well known among doctors that some patients don''t follow the directions for taking drugs. Some use drugs in combination with alcohol or take more than the recommended dosage, he said.

"It''s a safe and useful drug when taken as directed," Mullins said.

Steinberg couldn''t agree more. "We think it''s a very safe and effective drug. It''s been shown to be a safe and effective drug over the years," he said.

However, both doctors said Ambien should not be the first method used to treat insomnia; rather, it should be the last.

First, when a patient comes into a doctor''s office to discuss a sleeping problem, the doctor should provide proper sleep hygiene tips and instruct the patient to try this first.

"The best thing for insomnia is changing habits that don''t contribute to good sleep hygiene," Broyles said.

Tips for a good night''s sleep include:

Avoid caffeine before bedtime.

Avoid alcohol before bedtime. "It actually interferes sometimes with the natural sleep cycle. It doesn''t produce the best quality and most restful sleep," Mullins said.

Try to go to bed at a regular time.

If you can''t fall asleep in the first 30 minutes, get out of bed, relax or read and then try again. "The idea is to associate being in bed with sleeping," Mullins said.

Get exercise daily.

Eat at regular times.

Don''t watch television in the bedroom.

If the sleep hygiene guidance doesn''t work, a doctor should next suggest that a patient use over-the-counter medications, which include Tylenol PM, Unisom and Benadryl. These medicines contain diphenhydramine, an antihistamine, which is used to induce sleep. There can be a downside to using some of these remedies; some people might still feel groggy and/or tired in the morning, Mullins said.

If all of these methods fail, Ambien — the leading prescription sleep drug in the U.S. — is then the next step.

In 2005, there were 43.1 million prescriptions written in the U.S. for all prescription sleep medicines. There were 26 million prescriptions written for Ambien, which accounted for 58 percent of all prescriptions written for prescription sleep drugs, Mullins said.

According to Mullins, Ambien is number one for several reasons: It has been around longer, has had time to establish its niche in the market, was the first in a new class of drugs and physicians have more experience with Ambien. Ambien has been on the U.S. market for 13 years, which is longer than Sonata by about six years and much longer than Lunesta, which has been available for about one year, Mullins said.

Ambien is designed for and approved for use by adults for short-term insomnia. As with any drug, there are advantages and disadvantages.

Those who take Ambien can experience difficulty with cognitive ability, short-term amnesia, possible hallucinations, lethargy, dizziness, lightheadedness and may develop a dependence on the drug, medical experts said.

However, on the flip side, Ambien is safe and effective if used as directed. "It usually works well with few problems," Mullins said.

To have the best results with Ambien, the drug should be taken properly as directed by the doctor.

If a patient is taking other medicines, he should consult the doctor or pharmacist first before taking Ambien. This will prevent drug interactions, which could cause Ambien''s effects to last longer or work less effectively.

Ambien "works well in people who have mild to severe insomnia. It can get somebody back on track quickly," Broyles said. "I think (Ambien) is a safe medicine to use at this point."