Opioids and frequency counts in the US Food and Drug Administration Adverse Event Reporting System (FAERS) database: a quantitative view of the epidemic

The U.S. Food and Drug Administration Adverse Event Reporting System (FAERS), contains information on adverse drug events and medication error reports submitted to the FDA through the MedWatch program. A significant number of adverse events reported in the FAERS database have been for opioid use. The objective of this study was to determine the frequency counts and associated deaths of opioid drug names in the FAERS database.

Drug data were obtained from the DRUG and OUTCOME files in the database. Drugs identified included: morphine, fentanyl, oxycodone, hydrocodone, tramadol, hydromorphone, methadone, codeine, oxymorphone, meperidine, propoxyphene, diphenoxylate, and heroin. Frequency counts and concomitant deaths of opioid drug names were determined via the MySQL database management system.

Fifteen different opioid drugs identified in the FAERS database were associated with ADEs, including death, and 3 drugs (oxycodone, hydrocodone, fentanyl) accounted for more than half of the reports. The highest frequency count value was 158,181 for oxycodone, which represents approximately 20.2% of the frequency counts for the opioids. The lowest frequency count value was 2,161 for dextromethorphan, which represents approximately 0.3% of the total. The opioid with the highest proportion of deaths to drug count was heroin (71.8%), followed by dextromethorphan (55.6%), methadone (37.2%), morphine (26.8%), and propoxyphene (23.7%).

The FAERS database represents an important source for detection and reporting of adverse drug events (ADEs), in particular the opioids and related drugs. It remains a challenge to estimate the true incidence of ADEs for this class of drugs in the general population.