Ambien is an over-the-counter drug used to help people get to sleep and stay asleep. Chronic sleep disorders, also known as insomnia, are estimated to affect about 50 to 70 million Americans.

Picture taken by K3i8c84media.

Image of various zolpidem pills.

But the active ingredient in many of these insomnia medications, zolpidem tartrate, is also landing many users in the emergency room with adverse reactions.

A federal report says emergency room (ER) visits among those taking zolpidem jumped nearly 220 percent from 2005 to 2010.

USA Today reports on the Substance Abuse and Mental Health Services (SAMHSA) report which compiled adverse event reports from 2005 to 2010 collected by a public health hospital surveillance system, the Drug Abuse Warning Network.

It reported there were 19,487 ER visits related to zolpidem which is also found in Ambien CR, Edluar, Sonata and Zolpimist. All have received FDA approval to treat insomnia.

Complications included drowsiness and dizziness in the daytime, agitation, sleep-walking, sleep-driving, hallucinations and falling asleep while driving, says the SAMSHA report. A Wisconsin television station tells the story of a teen taking Ambien who went into the basement and shot off his knee cap. Other reports say users have prepared meals and used the microwave while sleeping. Tiger Woods confessed to a recreational romp while using the drug, while U.S. Rep. Patrick Kennedy blamed it on an auto accident.

The drug maker, Sanofi-Aventis, says Ambien is a safe and effective treatment for insomnia.

Since 74 percent of the users recorded in 2010 were age 45 or older and 68 percent were women, last January, the FDA recommended cutting in half the recommended dosage for women and for prescriptions for users age 65 or older. The same action was not required for men taking zolpidem.

Combining drugs or using alcohol with sleep medications is discouraged, especially anti-anxiety medications or narcotics. Drug combining has the potential to enhance the sedative effects of the drug.

The report found in 37 percent of the ER visits, zolpidem was combined with other drugs.