Data Show Significantly Higher Gabapentin Use in SUD Treatment Settings

Gabapentin prescribing has increased in substance use disorder (SUD) treatment settings despite a lack of strong evidence for its utility, according to authors of research published in Drug and Alcohol Dependence. Although rates of gabapentin use outside a prescription were nearly double those for prescribed use, this appears to be decreasing over time.¹

What Is Gabapentin and What Does It Treat?

Gabapentin is used to help control partial seizures (or convulsions) in the management of epilepsy, as well as for postherpetic neuralgia pain management after herpes zoster infection. The agent works in the brain to prevent seizures and relieve nervous system–related pain, and is not recommended for use in routine pain resulting from minor injuries or arthritis.²

For epilepsy, 300 mg taken 3 times per day is recommended for adults and children 12 years and older, with dose adjustments allowed as needed and tolerated; the dose is typically no more than 1800 mg/d (600-mg doses 3 times per day). Doses for children aged 3 to 11 years are based on body weight and must be determined by health care professionals, with a starting dose of 10 to 15 mg/kg of body weight per day and divided into 3 doses.²

For postherpetic neuralgia, 300 mg as a single dose in the evening is recommended for adults, with dose adjustments made by a health care professional based on each patient’s needs and tolerance. Similar to management of seizures, the dose is typically not more than 1800 mg/d.²

What Did the Study Investigate?

Off-label gabapentin prescriptions have increased to manage withdrawal or comorbidities in SUD treatment, despite gaps in evidence and corresponding increases in nonmedical use. The study, published in Drug and Alcohol Dependence, aimed to assess the prevalence and temporal trends in the use of gabapentin with or without a prescription among those in substance use treatment settings, along with associated demographics, comorbid conditions, and substance use patterns.¹

“I have been involved in SUD research for nearly 2 decades, particularly opioid use disorder. Recently, I have taken an interest in gabapentin for several reasons. Primarily, we have seen gabapentin prescriptions drastically increase in recent years for a range of conditions that are ‘off-label’ of its indications. As we know from the prescription opioid crisis, as prescriptions for a drug with psychoactive effects increase, so will its diverted use. And we’ve seen a complementary rise in nonprescribed use of gabapentin,” study author Matthew S. Ellis, PhD, MPE, assistant professor in the Department of Psychiatry, Washington University School of Medicine in St Louis, explained in an email interview with Pharmacy Times. “This is particularly important in the context of opioid use, as research from the pain sector has shown increases in the risk of respiratory depression when opioids and gabapentin are prescribed together. So, it follows that there are risks for nonprescribed use of opioids and gabapentin as well, making this a drug of interest.”

This retrospective, serial cross-sectional study analyzed 206,161 urine drug tests (UDTs) from 2053 SUD settings across the US from January 1, 2016, to October 31, 2023. UDT specimens are voluntarily submitted by practice specialties that include facilities specializing in addiction medicine, methadone, buprenorphine, inpatient, outpatient, and general addiction-related services. The specimens were analyzed by liquid chromatography–tandem mass spectrometry to assess positivity for gabapentin and other prescription and illicit drugs, with prescribed medications documented in requisitions.¹

Multivariable regression assessed characteristics/diagnoses associated with gabapentin use with and without a prescription. The data analysis included patient characteristics—with the exception of race—as well as the collection date of the UDT specimen and UDT results.¹

Gabapentin was prescribed to approximately 5.9% of the sample, increasing from 3.9% in 2016 to 7.6% in 2023. Use of gabapentin without a prescription was identified in 11.3% of the sample, decreasing from 15.2% to 9.9%. Gabapentin prescribing was associated with anxiety/mood disorders, insomnia, pain, and sedative, alcohol, or stimulant SUDs. Use without a prescription was associated with anxiety/mood disorders and sedative or opioid SUDs. Detection was higher across all illicit substances among those engaged in gabapentin use without a prescription.¹

“Gabapentin is often seen by clinicians as a safer alternative to benzodiazepines and opioids to manage comorbid conditions. Add to that its seeming utility to manage a range of conditions for individuals who have multiple conditions, [and] then it can seem like an optimal choice; however, it’s important that we build an evidence base first supporting these decisions. While it has a fairly robust evidence base for alcohol use disorder, it is lacking for all other use disorders, making the decision to prescribe a psychoactive drug, despite it being preferable to opioids and benzodiazepines, still questionable,” Ellis said. “The flip side of this is that those who are engaging in nonprescribed use appear to find benefit with gabapentin in self-treating their own comorbid conditions. But it is a fine line between self-treatment and engaging in nontherapeutic use, particularly given its association with respiratory depression when taken with opioids.”

Furthermore, the findings indicated that 12,064 (5.9%) of patients had a documented prescription for gabapentin, of whom 73.0% tested positive for gabapentin in their UDT. Males were less likely to be prescribed gabapentin than females (aOR, 0.71; 95% CI, 0.68-0.73; P < .001), and those 55 years and older had the highest odds of being prescribed gabapentin compared with the 18- to 24-year-old population (aOR, 2.07; 95% CI, 1.90-2.25; P < .001). Those with Medicare (aOR, 1.59; 95% CI, 1.47-1.73; P < .001) and private insurance (aOR, 1.35; 95% CI, 1.29-1.41; P < .001) were more likely to be prescribed gabapentin, whereas uninsured individuals (aOR, 0.70; 95% CI, 0.64-0.76; P < .001) had lower levels of gabapentin prescribing than Medicaid. Patients receiving buprenorphine were also more likely to be prescribed gabapentin (aOR, 2.69; 95% CI, 2.54-2.84; P < .001).¹

“[What most surprised me was] the fact that twice as many individuals had nonprescribed use vs prescribed use. I expected the rates to be similar, not a doubling. This suggests significant diversion of gabapentin. But also surprising was the lack of differences between those prescribed and not prescribed. This suggests that there is no clear group that stands out as being more or less likely to use gabapentin nonmedically. This needs to be investigated more, but given similarities in comorbidities, this may be reflecting a lack of integrated care rather than misuse for euphoric or pleasure-seeking. But of course, that is simply a hypothesis that needs to be investigated further,” Ellis said.

What Should Pharmacists Take Away From These Findings?

The authors wrote that, despite a lack of strong evidence for its utility in these populations and for specific use disorders, gabapentin prescribing has significantly increased for those entering SUD treatment settings. The prescribing of gabapentin was generally associated with multiple physical and mental health comorbidities, emphasizing a need for stronger integrated care plans for patients in SUD treatment settings, especially older adults. Although the rate of gabapentin use without a prescription was nearly double the rate of those who were prescribed gabapentin, this trend appears to be decreasing, but the authors emphasized that further research is needed to understand the drivers of gabapentin use outside of a prescription (eg, role of polysubstance use, gaps in care).¹

“What I most want individuals to take away from these findings is that we are in no way trying to demonize gabapentin,” Ellis said. “What we are doing is highlighting the gap in the evidence base in understanding its risks vs benefits for those with SUD. The fact that twice as many individuals tested positive for nonprescribed use should give pharmacists and addiction specialists pause to consider why and how that may be the case.”

REFERENCES

1. Ellis MS, Whitley P, Passik SD. Use of gabapentin with or without a prescription in substance use treatment settings: a national analysis of urine drug testing data, 2016–2023. Drug Alcohol Depend. 2026;279:113020. doi:10.1016/j.drugalcdep.2026.113020

2. Gabapentin (oral route). Mayo Clinic. Updated February 1, 2026. Accessed March 13, 2026. https://www.mayoclinic.org/drugs-supplements/gabapentin-oral-route/description/drg-20064011