Substituting gabapentin for opioids has significant downsides

Although gabapentin is effective at relieving some types of neuropathic pain, namely diabetic neuropathy and postherpetic neuralgia, it is notably ineffective for treating other types, such as radicular low back pain. A 2019 editorial in American Family Physician warned of potential unintended consequences of using gabapentinoids (gabapentin and pregabalin) as alternatives to opioids for pain management. The authors observed that "as many as one in three patients taking therapeutic doses will experience dizziness or somnolence"; also, the U.S. Food and Drug Administration issued a safety communication about gabapentinoids causing serious breathing problems in patients with chronic respiratory diseases and older patients.

Illicit use of gabapentin is playing an increased role in opioid-related overdoses, according to a May 2022 report from the Centers for Disease Control and Prevention. The report found that between 2019 and 2020, toxicology results detected gabapentin in almost 10% of fatal overdoses recorded in 23 states and Washington, DC. Misuse of gabapentin occurs for several reasons: "to enhance the effects of opioids," "to achieve a 'high' when preferred substances [are] unavailable," and "to self-treat withdrawal or pain."

A recent cohort study in JAMA Internal Medicine examined gabapentin use in the perioperative period (within 2 days after major surgery) and in-hospital adverse events in nearly 1 million patients aged 65 years or older. More than 3 in 4 patients underwent orthopedic surgeries. Overall, 12.3% were prescribed gabapentin perioperatively. Those patients were statistically more likely to experience delirium, receive a new prescription for an antipsychotic drug, and develop pneumonia than gabapentin non-users. In persons using gabapentin, the risk of delirium was higher with chronic kidney disease and a high burden of comorbidities.

An accompanying commentary pointed out that the study results "are consistent with what is now a growing body of literature suggesting that gabapentin may not be the windfall medication for perioperative pain management that surgeons hoped it might be for decreasing opioid use," particularly in older adults:

We need to unwind the automaticity of gabapentin use in the perioperative period. For example, in this study, 80% of gabapentin users received gabapentin on the day of surgery, suggesting that it was started prior to any patient report of pain, representing an opportunity to de-escalate gabapentin use for some patients. Second, engaging patients and caregivers in their care could allow us to better manage expectations for pain control in the perioperative period. A multimodal approach needs to be patient centered and flexible. Finally, aside from swapping out one potentially problematic medication for another, nonpharmacological techniques that might be used to treat pain should be considered.