A retrospective cohort study published in Regional Anesthesia and Pain Medicine found that off-label gabapentin prescriptions did not reduce opioid dosage in patients with chronic opioid use. The study assessed 172,602 commercially insured patients with chronic opioid use who received a new off-label gabapentin prescription between January 1, 2010, and June 30, 2019. The majority of patients had arthritis (82.3%) or back pain (68.5%), with 28.7% having an anxiety diagnosis and 19.4% having an alcohol or substance use disorder.
Opioid dosages were measured using oral morphine equivalents (OME) per day after adding the new off-label gabapentin prescription. The new off-label gabapentin prescription was associated with a decrease in opioid dosage in 38.8% of patients 6 months after initiating the prescription, while an increase in opioid dosage was reported in 47.0% of patients. No change in opioid dosage was reported in 14.2% of patients.
The study's limitations include the retrospective nature of the study, the fact that gabapentin and opioid prescriptions reflect fill rates but may not reflect actual consumption, and the study of employer-sponsored health insurance claims may not be generalizable to Medicare and Medicaid recipients or the uninsured.