We really like our Xanax, study says

Alprzolam (Xanax) is now the second-leading cause of impaired driving in Alabama, after alcohol.

(TOM PENNINGTON)

It took four months to indict Matthew Ray Tidwell for driving under the influence in the rollover crash that killed his 7-year-old daughter in December.

It might have been sooner if he had alcohol in his system. But instead, prosecutors allege that Tidwell was using alprazolam (Xanax) and codeine when he ran off the road in Lauderdale County. The same drug appeared in the toxicology report for Caren Gayle Rush, who was convicted last year for manslaughter in a 2012 crash that killed a former high school softball star.

Alprazolam, the generic name for the anti-anxiety drug Xanax, surpassed marijuana in 2011 as the second-leading cause of impaired driving in Alabama after alcohol, according to data from traffic stops compiled by the Department of Forensic Science. The data did not include car crashes, but Curt Harper, toxicology discipline chief for the Alabama Department of Forensic Science, said he believed those figures would be similar.

"Each state sort of has its problem child, and Xanax is ours," Harper said.

Last year, alprazolam was found in 29 percent of DUI cases, compared to 23 percent for marijuana. The percentage of DUI cases caused by alprazolam has held steady for the past three years, according to the data.

Proving that a person is impaired by alprazolam is different than establishing intoxication from alcohol, Harper said. If a subject tests positive for a high blood alcohol level, prosecutors don't usually have to depend as heavily on evidence of impairment, which may be measured by a field sobriety test and other physiological symptoms.

The Alabama Law Enforcement Agency has specially-trained officers called Drug Recognition Experts who are called upon to assess impaired drivers who are using substances other than alcohol. They measure physiological symptoms, such as pupil dilation and body temperature, and mental performance to determine what kind of drug a person may be using. Harper said he became the first toxicologist trained as a drug recognition expert during a recent three-week session that produced 10 new experts.

"Impaired driving from prescription drugs is not a new problem; it has been around for years," wrote Sgt. Steve Jarrett, public information officer for the Alabama Law Enforcement Agency, in an e-mail. "However, in recent years Law Enforcement has been better trained to detect people under the influence of drugs."

Alprazolam has been the most-commonly prescribed psychiatric drug since 2005, with 48.5 million prescriptions in 2013, according to PsychCentral. In Alabama, alprazolam was the 14th most prescribed drug overall in the Medicare Part D program, with 359,781 claims in 2013, according to ProPublica.org.

Alprazolam was introduced in 1981 under the brand name Xanax, and is one of the most widely-abused prescription drugs, according to a 2006 study by the Substance Abuse and Mental Health Services Administration. Its widespread availability could account for its increasing presence in impaired drivers, Harper said.

Peter Hendricks, chemical psychologist at UAB, said alprazolam is the most widely-abused benzodiazepine, which are a class of drugs that treats anxiety and also includes Valium and Klonopin.

"What I tell my students is that benzodiazepines are actually alcohol in pill form," Hendricks said.

Like alcohol, alprazolam increases feelings of relaxation, sleepiness and lightheadedness, he said. In controlled driving tests, subjects who have received 1 milligram of alprazolam showed increased weaving, and several driving tests had to be stopped because subjects became too drowsy to continue.

Harper said controlled driving tests can't necessarily be compared to typical driving performance. And subjects who aren't used to taking alprazolam would show greater effects of the drugs than those who have been on them for an extended amount of time.

Most drunk driving laws are based on data from large studies of alcohol level and car crash data, Harper said. Those studies initially set the limit for impairment at .15 blood alcohol concentration, then .10 and now .08. Researchers are just beginning to gather similar data for marijuana, but there are no equivalent studies for other drugs.

When Harper testifies in court, he often uses data that shows that the level of the drug in a driver's system is much higher than therapeutic levels. But the drug can affect driving ability even in those who are taking it as prescribed, and most doctors advise patients to avoid driving until they know how they are affected by the drug.

"You can be impaired even if it's in the therapeutic range," Harper said.

People typically take a dose of alprazolam several times a day, Hendricks said. There is some controversy about whether the drug is habit-forming, but doctors have become increasingly concerned about addiction and have begun to restrict prescriptions, Hendricks said.

Since doctors have already begun to cut back on alprazolam prescriptions, Hendricks said he does not expect the problem of abuse to grow in coming years. Although they can improve the symptoms of anxiety, benzodiazepines do nothing to address the root cause of the disorder, Hendricks said.

"I have no doubt that people who use them for anxiety get some relief from these drugs," Hendricks said. "But we should steer away from medicines that require daily use for an extended period of time."

Article updated at 1:37 p.m. on Monday, June 22 to reflect the new name of the Department of Public Safety, which is now the Alabama Law Enforcement Agency.