ADE-related ER visits on the rise

March 18th, 2015

Following years of data on adverse reactions to prescription medications, investigators from Johns Hopkins University and the Centers for Disease Control and Prevention set out to study how many such reactions would result in ER visits annually across the United States.

Data was collected by analyzing the national prescription drug surveillance records from 2009 to 2011, as well as looking at the data from 63 hospitals participating in the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey.

The study found that mishaps (accidental overdose or adverse reaction) from psychiatric drugs contribute to nearly 90,000 ER visits in the United States annually. Of these visits, about one in five patients require hospitalization.

The most common adverse reactions occurred after overdosing on antidepressants and/or sedatives, specifically Ambien, which was tied to more than 10,000 of the 90,000 ER visits annually.

The sedative contained in Ambien and other prescription medications, zolpidem tartrate, has been implicated in 12% of ER visits among U.S. adults and one in five visits among elderly adults, contributing to falls and head injuries among this patient population. In addition to falls and head injuries, other complaints included mental disturbances, heart-related problems, and intestinal discomfort.

“Psychiatric medications are implicated in many [adverse drug events, or ADEs] treated in U.S. [emergency departments]. Efforts to reduce ADEs should include adults of all ages but might prioritize medications causing high numbers and rates of emergency department visits too,” wrote lead investigator Lee Hampton.

Last year, the Food and Drug Administration approved label changes for pills containing zolpidem tartrate, recommending lower doses because of adverse reactions. The manufacturer, Sanofi, continues to warn consumers that the drug may cause “impaired alertness and motor coordination,” also recommending that doctors “caution patients against driving and other activities requiring complete mental alertness the morning after use."

"The FDA's recent efforts to modify recommended dosing regimens hold promise for reducing zolpidem-related problems," the investigators wrote. “But they also said doctors can help by recommending that patients use other insomnia treatments first, including better sleep habits and behavior therapy.”

In addition to the visits related to Ambien (10,212 visits), the researchers found that nearly 60% of the 90,000 ER visits were related to nine specific psychiatric medications, taken either alone or in combination. Two other drugs implicated in the most ER visits (following Ambien) included:

* Seroquel (6,900 visits), an antipsychotic drug used to treat people with bipolar disorder and schizophrenia * Xanax (5,616), an anti-anxiety drug, along with its generic forms.

The study also found that lithium salts had the most ER visits relative to the number of doctor's visits for a prescription — for every 10,000 doctor's visits for a prescription for lithium salts, there were about 16 ER visits.

"Attempts to reduce the use of psychiatric medications when risks outweigh benefits have had mixed success, but the current burden of [adverse drug events] from therapeutic use of psychiatric medications … suggests that such efforts should continue," said the researchers.