Nonprescription and Prescription Drugs Cause Poisonings

Jennifer Garcia

October 09, 2012

October 9, 2012 — A new study has found that nonprescription and prescription drugs are equally responsible for drug poisonings in the United States and has identified new trends in prescription drug abuse. The study, which analyzed data from the second annual report of the Toxicology Investigators Consortium (ToxIC), was published online October 2 in the Journal of Medical Toxicology.

Researchers led by Timothy Wiegand, MD, from the University of Rochester Medical Center in New York, evaluated cumulative data on 10,392 toxicology cases collected during 2011 and compared the entries with data from 2010.

The authors found that over half (53%) of toxicology consultations in 2011 occurred in emergency departments and were primarily for cases of pharmaceutical overdose (48%), which included both intentional (37%) and unintentional (11%) exposures. Consultation rates for prescription vs nonprescription drug abuse cases were similar in 2010; however, there was an increase in the number of prescription drug abuse consultations in 2011 compared with the number of nonprescription drug consults.

The most common classes of agents for which toxicology consultations were requested were "sedative–hypnotics (1,492 entries in 23 % of cases), non-opioid analgesics (1,368 cases in 21 % of cases), opioids (17 %), antidepressants (16 %), stimulants/sympathomimetics (12 %), and ethanol (8 %)." These groups include muscle relaxants, sleeping pills, nonopioid pain relievers such as acetaminophen and ibuprofen, and opioid pain relievers such as oxycodone.

"Much of the current concerns about prescription drug abuse have centered on opioids, and while opioids are certainly of greater concern in regards to morbidity and mortality related to overdose, the data reported herein suggest that emphasis should also be placed on the sedative hypnotics," Dr. Wiegand and colleagues write.

The number of cases involving psychoactive drugs of abuse increased in 2011. Marijuana was involved most frequently, with 123 cases (34%) in this group compared with just 27 cases in 2010. Dextromethorphan was the next most common, at 33%, representing almost double the number of cases from 2010.

"Our data also suggest that while medication abuse is a major problem, restricting our concerns to prescription drug abuse fails to acknowledge the major role of [over-the-counter] agents," the researchers note.

The study authors also document an important increase in cases involving designer drugs such as psychoactive bath salts, which doubled the number of stimulant/sympathomimetic-related cases from 6% in 2010 to 12% in 2011. They also report a 3-fold increase from 2010 in cases involving synthetic cannabinoids.

There were 35 reported deaths in 2011 resulting from medication overdose, most often involving opioids and analgesics either alone or in combination with other drugs. Six of the 10 opioid-related deaths were attributed to oxycodone, and acetaminophen was identified in all 8 of the analgesic-related deaths.

The authors acknowledge that the data reflect only those cases cared for in a medical setting and may therefore be biased toward cases in which there was greater morbidity. History of exposure is also self-reported, and accuracy of the data may also pose a limitation to the study.

"ToxIC allows extraction of information from medical records making it the most robust multicenter database on chemical toxicities in existence," Dr. Wiegand and colleagues write.

"As demonstrated by the trends identified in psychoactive bath salt and synthetic cannabinoid reports, the Registry is a valuable toxicosurveillance and research tool," they conclude.

Funding for this study was provided by the American College of Medical Toxicology. The authors have disclosed no relevant financial relationships.

J Med Toxicol. Published online October 2, 2012. Abstract