(CNN) -- Alprazolam, the prescription sedative more commonly known by its brand name, Xanax, is being implicated in a spiraling number of emergency room visits, according to a new report by the Substance Abuse and Mental Health Services Administration.
Over the past few years, the number of ER visits associated with misuse of the drug more than doubled. In 2005, the number of patient cases involving Xanax was 57,419, and by 2011 (the last year for which there is data), there were 123,744.
"We have been clamping down on opiates (prescription painkillers) but Xanax is becoming a fast-riser in the game," said Dr. Howard Mell, an emergency room physician based in Cleveland, Ohio.
"It's not even a little surprising," he said of the new figures. "I wish it was."
In 2011, 1.2 million visits to the emergency room involved prescription drug misuse and abuse. And, according the report, alprazolam was involved in 10% of those visits.
Part of alprazolam's fast rise: It is a go-to anti-anxiety drug for psychiatrists and primary care physicians. According to recent studies, Xanax was the most commonly prescribed psychiatric medication in 2011.
And with its addictive qualities, abuse is common, said Mell, a spokesman for the American College of Emergency Physicians.
The most common drug combinations he encounters in ER patients are Xanax and alcohol, and Xanax combined with prescription opiates like hydrocodone and oxycodone.
According to the SAMHSA report, in 81% of cases, alprazolam was mixed with another drug (including alcohol).
"Alprazolam...has been shown to be significantly more toxic than other benzodiazepines," a class of anxiety medications that includes Valium, "if more than the prescribed amount is taken," according to the report.
The impact -- what leads patients to the emergency room -- is the sedating effect of each of these drugs. When one sedative (Xanax) is added to another (alcohol or painkillers) there is what is called a synergistic effect, with each drug amplifying the other.
To use a mathematical analogy -- instead of 1+1 equaling 2, 1+1 equals 5. The worst case scenario for a patient is that he or she stops breathing.
"If you're someone taking Xanax and you take an extra before going out Saturday night, then have a couple of mixed drinks, it's going to hit you much faster," said Mell. "It's going to cause an interaction that could be deadly."
Mell says his typical patient is not the "pimply-faced" kid you might expect to be abusing drugs. His overdose patients, he says, are soccer moms, local politicians and business leaders.
"They think because the drugs (are) given out by doctors that they can handle it," he said. "They figure 'I wouldn't put anything in my medicine cabinet that's unsafe to take,' and that's just not true."
Between 2005 and 2011, according to the SAMHSA report, the age group most likely to show up in the ER as a result of alprazolam was 25 to 34 year olds. In 2005, about 12,731 visits were among that age group, but by 2011 that number had risen to 39,651.