Skip to main content
NCBI home page
NIHPA Author Manuscripts logoLink to NIHPA Author Manuscripts
. Author manuscript; available in PMC: 2021 Mar 1.
Published in final edited form as: J Subst Abuse Treat. 2019 Dec 13;110:37–41. doi: 10.1016/j.jsat.2019.12.007

Prescribed and Non-Prescribed Gabapentin Use among Persons Seeking Inpatient Opioid Detoxification

Michael D Stein a,b, Shannon R Kenney a,c, Bradley J Anderson a, Micah T Conti d, Genie L Bailey c,d
PMCID: PMC6981248  NIHMSID: NIHMS1547545  PMID: 31952626

Abstract

Background

Persons with opioid use disorder (OUD) are at increased risk for gabapentin misuse. Rising rates of concomitant gabapentin-opioid use in the U.S. are concerning given heightened risk of fatal overdose.

Objective

To examine predictors of ever using gabapentin among persons seeking treatment for opioid use and to assess if reasons for gabapentin use differed by gender and how gabapentin was procured (prescribed, non-prescribed, or both).

Method

Persons with OUD were recruited from a managed withdrawal program. T-tests and Pearson χ2 tests of independence were used to compare reasons for gabapentin use by gender and source of acquisition.

Results

Among participants (n=401; 69.1% male, 84.5% White, 86.8% sought treatment for heroin use, 90.0% insured), female gender, higher educational attainment, injection drug use (IDU), history of overdose, and chronic pain were associated with gabapentin use. Overall, reasons for use were similar across genders among those reporting a history of gabapentin use (65.8%), although males were more likely to use to get high than females. About half (47.0%) reported only using gabapentin that was not prescribed, 20.5% had only used prescribed gabapentin, and 32.5% reported prescribed and non-prescribed use. Persons prescribed gabapentin were most likely to use it to control pain (81.5%); for those using diverted gabapentin only and those reporting both prescribed and non-prescribed gabapentin use, the most common reasons for intake were to: get high, increase effects of heroin, substitute for opioids, and help with opioid withdrawal.

Conclusions

In this sample of people with OUD entering inpatient detoxification program, a majority reported a history of gabapentin use, with most using diverted gabapentin. The range of reasons for gabapentin use point to the need to better understand why co-use is common.

Keywords: Gabapentin, Opioids, Heroin, Overdose, Harm Reduction

1. INTRODUCTION

Gabapentin is a medication approved for the adjunctive treatment of complex epilepsy and postherpetic neuralgia in adults. Although it is a non-controlled substance at the federal level, many states have passed legislation either to designate it as a scheduled substance at the state level, or to mandate reporting to prescription drug monitoring programs (Peckham, Ananickal, & Sclar, 2018). Gabapentin is most often prescribed off-label for diverse psychiatric diagnoses including generalized anxiety and mood disorders insomnia, migraines, and as an alternative to opioid therapy for chronic pain (Fukada, Kohler, Boon, Austin, & Krahn, 2012; Peckham, Evoy, Ochs, & Covvey, 2018; Throckmorton & Woodcock, 2018). Despite the lack of efficacy trials for off-label gabapentin use (Moore, Wiffen, Derry, Toelle, & Rice, 2014 for review; Peckham, Evoy, Ochs, et al., 2018) and evidence suggesting its abuse liability (Evoy, Morrison, & Saklad, 2017 for review), prescribing rates have increased 64% from 2012 to 2016 to make it the sixth most prescribed drug in the U.S. (Quintiles IMS Institute, 2019).

Although the likelihood for gabapentin abuse appears relatively low when prescribed to people without a history of opioid use (Peckham, Evoy, Covvey, et al., 2018), it is estimated that half of patients prescribed gabapentin are concurrently prescribed an opioid analgesic (Throckmorton, Gottlieb, & Woodcock, 2018). Not only do opioid users demonstrate six-fold greater odds for sustained high-dose gabapentin use (Peckham, Fairman, & Sclar, 2018), but international and national studies show exponential increases in gabapentin misuse among persons with opioid use disorder (OUD) (Smith, Havens, & Walsh, 2016; Smith, Lofwall, & Havens, 2015). Between 2008 and 2014, Smith et al (2014) showed a 2950% increase in gabapentin use to get high among Kentucky residents using non-prescribed opioids. Concomitant gabapentin-opioid use is associated with misuse and serious health risks, including inpatient hospitalizations (Peckham, Fairman, et al., 2018) and fatal overdose (Evoy et al., 2017 for review). Gabapentin-opioid use increases risk for fatal overdose by an estimated 49% relative to controls (Gomes et al., 2017), and toxicology testing of overdose decedents show that 79.0% - 91.4% of gabapentinoid deaths involve opioids (Hakkinen, Vuori, Kalso, Gergov, & Ojanpera, 2014; Lyndon et al., 2017) and 26% of opioid overdose deaths test positive for gabapentin (Slavova et al., 2018).

Despite the public health concerns raised by combined gabapentin-opioid misuse, research examining predictors and reasons for co-use are lacking, particularly among those with public insurance. Predictors found to be associated with gabapentin-opioid overuse in commercially insured people include a history of opioid or other drug use disorders, a history of attending withdrawal management programs psychiatric diagnosis, and pain (Bastiaens, Galus, & Mazur, 2016; Peckham, Evoy, Covvey, et al., 2018). In another study of a dually diagnosed correctional population, gabapentin use was higher in individuals with OUD than in those without, although the predictors and reasons for this co-use were not examined (Bastiaens, Galus, & Mazur, 2016). However, the relationship between gender and likelihood for gabapentin misuse is unclear. While some studies have found that females, relative to males, appear more susceptible to gabapentin misuse (Pauly, Slavova, Freeman, Lofwall, & Talbert, 2017), overdose (Klein-Schwartz, Shepherd, Gorman, & Dahl, 2003; Slavova et al., 2018; Wills et al., 2014), and gabapentin-opioid co-use (Peterson, 2009), other large-scale studies report higher incidence of gabapentin misuse in males (Peckham, Evoy, Covvey, et al., 2018), and still other studies find no gender differences (Smith et al., 2016). Explicating how gabapentin-opioid use and reasons for use may differ by gender in an opioid dependent sample may provide valuable insight for those interested in reducing harm in this high-risk population.

Studies have identified a variety of patient-reported reasons for misusing gabapentin, many of which relate to concurrent opioid use. These reasons include achieving a psychoactive high, controlling mood or anxiety symptoms, potentiating medication for OUD or other substances, harming oneself, controlling pain, reducing opioid cravings, managing opioid withdrawal, and substituting gabapentin for opioids when opioids are unavailable (Baird, Fox, & Colvin, 2014; Barrueto, Green, Howland, Hoffman, & Nelson, 2002; Buttram, Kurtz, Dart, & Margolin, 2017; Klein-Schwartz et al., 2003; Kruszewski, Paczynski, & Kahn, 2009; Peterson, 2009; Reeves & Ladner, 2014; Smith et al., 2015; Victorri-Vigneau, Guerlais, & Jolliet, 2007). Still, few studies have examined a comprehensive list of reasons for use among persons with OUD, or of factors associated with reasons for use. Moreover, research has yet to address how reasons for gabapentin use may differ by gender and how gabapentin is acquired. Gabapentin for both label and off-label indications is increasingly prescribed in the U.S. (Peckham, Evoy, Ochs, et al., 2018) despite escalating diversion (i.e., the illicit transfer of prescribed gabapentin) rates (Buttram et al., 2017). While Buttram et al. found that those obtaining diverted gabapentin use it in conjunction with opioids to increase their high, particularly with heroin, other reasons for co-use have not been explored.

Based on existing studies, we predicted that prior withdrawal management, younger age, female status, depressed mood, and anxiety would be associated with prior use of gabapentin. We also hypothesized that those reporting high-risk drug use (i.e., injection drug use (IDU), prior overdose) would be more likely to have ever used gabapentin. Finally, when examining reasons for use, we expected that respondents acquiring diverted, as opposed to prescribed, gabapentin would report using gabapentin to enhance the high of opioids or counteract opioid symptoms (e.g., withdrawal, cravings), whereas those who acquired gabapentin through prescription only would be more likely to report using the medication to control pain or mood/anxiety symptoms.

2. Materials and methods

2.1. Recruitment

Patients seeking inpatient opioid withdrawal management at Stanley Street Treatment and Resources, Inc. (SSTAR; Fall River, Massachusetts) were invited to participate in a survey research study. SSTAR provides evaluation, supervised symptom management using a methadone taper schedule, individual and group education and counseling, and aftercare case management (mean length-of-stay is 5.2 days).

Of 472 patients admitted to SSTAR for OUD from May 2018-March 2019, 65 refused study participation or were discharged before staff could perform an interview. Patients were included if they were 18 years or older, English-speaking, and able to provide informed consent. Of the 407 persons who completed a 15-minute, non-compensated face-to-face interview, six cases were excluded for missing data. Survey interviews were administered by non-treating research staff after admission. The current study sample is comprised of 401 persons. All study criteria were approved by the Butler Hospital Institutional Review Board.

2.2. Measures

In addition to age, gender, race, ethnicity, years of education, IDU (ever and past 30days), the following variables were assessed.

2.2.1. Detoxification Drug

Respondents were asked, “What is the primary drug you are detoxifying from?”

2.2.2. History of overdose

Respondents were asked if they had ever overdosed. Overdose (on any drug) was defined as “you were unarousable (couldn’t be woken) with shaking or calling your name because of the drugs you consumed.”

2.2.3. History of Withdrawal Management

Respondents were asked if they had “ever been in detoxification for opioids before.”

2.2.4. Chronic Pain

Respondents were asked if and where they had “any back, neck, headache, abdominal, joint, chest, or facial pain.” Those with affirmative responses were then asked how many weeks they had that pain. Respondents reporting specified pain for 24 or more weeks were coded as having chronic pain (Dahlhamer et al., 2018).

2.2.5. Gabapentin Use Sources

Respondents reporting ever using gabapentin were asked if they had ever been prescribed gabapentin or used non-prescribed gabapentin (i.e., bought gabapentin on the street; or borrowed, bought or used a friend or relative’s gabapentin). Gabapentin sources were categorized as prescribed or non-prescribed.

2.2.6. Reasons for Gabapentin Use

Respondents were asked if they had ever used gabapentin (yes or no) for a variety of reasons drawn from previous studies (see Table 2)

Table 2.

Reasons for Gabapentin Use by Gender. Cell Entries are n (%).

GENDER
Female (n = 99) Male (n = 165) p = a
To get high? 53 (53.5%) 109 (66.1%) 0.043b
To control pain? 77 (77.8%) 116 (70.3%) 0.185
To increase heroin effects? 40 (40.4%) 64 (38.8%) 0.795
To increase suboxone/methadone effects? 15 (15.2%) 24 (14.5%) 0.893
To substitute for opioids? 51 (51.5%) 91 (55.2%) 0.566
To help you sleep? 53 (53.5%) 79 (47.9%) 0.374
To help withdraw from opioids? 63 (63.6%) 108 (65.5%) 0.765
To help withdraw from alcohol? 8 (8.1%) 9 (5.5%) 0.400
To reduce opioid craving? 52 (52.5%) 95 (57.6%) 0.424
To control your mood/ anxiety? 67 (67.7%) 109 (66.1%) 0.787
To hurt yourself? 0 (0.0%) 0 (0.0%) NA
Because you were addicted to it? 13 (13.1%) 22 (13.3%) 0.963
To make you more talkative or sociable? 20 (20.2%) 43 (26.1%) 0.280
To increase energy and focus? 42 (42.4%) 84 (50.9%) 0.181
Open in a new tab
a

χ2 – test for differences in counts.

b

Males were significantly more likely to use gabapentin to get high than females (66.1% vs 53.5%, p = .041). Other reasons for gabapentin use did not vary by gender.

2.3. Analytical Methods

Descriptive statistics summarize the background characteristics of the sample, drug use behaviors, and pain. T-tests were used to examine differences in means and the Pearson χ2 – test of independence was used to compare these same background characteristics and behaviors of persons with and without a history of gabapentin use. Among persons with a history of gabapentin use, the χ2 – test was also used to compare males and females with respect to the likelihood of endorsing different reasons for gabapentin use.

3. Results

Participants averaged 34.5 (± 8.8) years of age, 30.9% were female, 84.5% were White, and 11.0% were Hispanic (Table 1). Mean years of education was 11.8 (± 2.0). In all, 65.8% of participants reported ever using gabapentin. About 86.8% reported heroin as the primary drug for which they were in managed withdrawal, 78.6% said they had previously been in managed withdrawal, 73.3% reported a history of IDU, and 60.6% had injected within the past 30-days. Approximately 59.9% reported a lifetime history of drug overdose. Approximately 44.4% of the sample reported pain lasting 24 or more weeks.

Table 1.

Background Characteristics by Gabapentin Use. Cell Entries are Means (± SD) or n (%).

EVER USED GABAPENTIN
Sample (n = 401) No (n = 137) Yes (n = 264) p = a
Years Age 34.5 (± 8.8) 35.7 (± 10.2) 33.9 (± 7.8) .053
Sex (Female) 124 (30.9%) 25 (18.2%) 99 (37.5%) <0.001
Race (White) 339 (84.5%) 118 (86.1%) 221 (83.7%) .525
Ethnicity (Hispanic / Latino) 44 (11.0%) 18 (13.1%) 26 (9.8%) .317
Years Education 11.84 (1.97) 11.49 (2.19) 12.02 (1.83) .011
Detox Drug (Heroin) 348 (86.8%) 115 (83.9%) 233 (88.3%) .226
Prior WM Ever (Yes) 315 (78.6%) 101 (73.7%) 214 (81.1%) .090
Ever IDU (Yes) 294 (73.3%) 89 (65.0%) 205 (77.7%) .006
IDU Past 30-Days (Yes) 243 (60.6%) 70 (51.1%) 173 (65.5%) .005
Ever Overdosed (Yes) 232 (57.9%) 64 (46.7%) 168 (63.6%) .001
Pain 24+ Weeks (Yes) 178 (44.4%) 48 (35.0%) 130 (49.2%) .007
Open in a new tab
a

T-test for difference in means or Pearson χ2 – test for independence.

Note. WM = Withdrawal management; IDU = injection drug use.

Persons reporting a history of gabapentin use were significantly more likely to be female (37.5% vs 18.2%; p < 0.001), had significantly (p = 0.011) higher mean years of education (12.0 vs 11.5 years), and were significantly more likely to have lifetime (p = 0.006) and past-month (p = 0.005) IDU. Gabapentin users were also significantly more likely to report a lifetime history of drug overdose (p = 0.001), and to report they had chronic pain (p = 0.007). Persons with and without a history of gabapentin use did not differ significantly with respect to any of the other background characteristics evaluated in Table 1.

As shown in Table 2, among persons with a lifetime history of gabapentin use, males were significantly more likely than females to report they had used the drug to get high (66.1% vs 53.5%; p = 0.043). However, males and females did not differ significantly with respect to the other reasons for gabapentin use. The most commonly cited reason for both males (77.8%) and females (70.3%) was to control pain. Another frequently endorsed reason was controlling anxiety and mood, which was endorsed by 66.1% of males and 67.7% of females. About 63.6% of females and 65.5% of males reported they had used gabapentin to help reduce the effects of opioid withdrawal.

Persons who had used only prescribed gabapentin, only non-prescribed gabapentin, and had obtained both prescribed and non-prescribed gabapentin were compared with respect to reasons for use (Table 3). Statistically significant (p < 0.05) between group differences were observed on 11 of the 13 reasons. For each comparison presented below the percentages represent those using prescribed gabapentin only, non-prescribed only, and both, respectively. Participants who had used only prescribed gabapentin were much less likely to say they used gabapentin to get high (16.7% prescribed only vs 72.6% diverted only vs 73.3% prescribed and diverted; p < 0.001), to increase the effects of heroin (14.8% vs 42.7% vs 50.0%; p < 0.001), to increase the effects of buprenorphine (Suboxone) or methadone (3.7% vs 16.1% vs 19.8%; p = 0.028), to substitute for opioids (22.2% vs 62.9% vs 60.5%; p < 0.001), to help withdraw from opioids (33.3% vs 71.0% vs 75.6%; p < 0.001), because they were addicted to it (1.9% vs 9.0% vs 25.6%; p < 0.001), to make them more talkative and sociable (0.0% vs 25.8% vs 36.0%; p < 0.001), and to increase energy and focus (9.3% vs 50.0% vs 68.6%; p < 0.001). Persons who had obtained non-prescribed gabapentin only had a lower rate of saying they used the drug to control pain than those who had only used prescribed gabapentin or those who had obtained the drug from both sources (62.1% vs 81.5% vs 83.7%; p < 0.001). These groups did not differ significantly with respect to endorsing use of gabapentin for sleep, or to help them withdraw from alcohol.

Table 3.

Reasons for Using Gabapentin by Source. Cells give n (%) endorsing the reason.

GABAPENTIN SOURCE(S)a
Reason Rx Only (n = 54) Non-prescribed Only (n = 124) Both (n = 86) p =b
To get high? 9 (16.7%) 90 (72.6%) 63 (73.3%) 0.000
To control pain? 44 (81.5%) 77 (62.1%) 72 (83.7%) 0.001
To increase heroin effects? 8 (14.8%) 53 (42.7%) 43 (50.0%) 0.000
To increase buprenorphine/methadone effects? 2 (3.7%) 20 (16.1%) 17 (19.8%) 0.028
To substitute for opioids? 12 (22.2%) 78 (62.9%) 52 (60.5%) 0.000
To help you sleep? 20 (37.0%) 64 (51.6%) 48 (55.8%) 0.085
To help withdraw from opioids? 18 (33.3%) 88 (71.0%) 65 (75.6%) 0.000
To help withdraw from alcohol? 3 (5.6%) 8 (6.5%) 6 (7.0%) 0.946
To reduce opioid craving? 15 (27.8%) 72 (58.1%) 60 (69.8%) 0.000
To control your mood/ anxiety? 29 (53.7%) 73 (58.9%) 74 (86.0%) 0.000
Because you were addicted to it? 1 (1.9%) 12 (9.7%) 22 (25.6%) 0.000
To make you more talkative or sociable? 0 (0.0%) 32 (25.8%) 31 (36.0%) 0.000
To increase energy and focus? 5 (9.3%) 62 (50.0%) 59 (68.6%) 0.000
Open in a new tab
a

Sources are prescription only, non-prescribed only, and both sources.

b

χ2 – test for differences in counts.

4. Discussion

The current study adds to the limited research examining the predictors and reasons for lifetime gabapentin use in a sample of persons seeking OUD withdrawal, and demonstrates that gabapentin use is common and often involves obtainment from a non-prescribed source. Gabapentin plays a role in many of the behaviors related to opioid use as it is ingested to get high, control pain, substitute for opioids, mitigate opioid withdrawal, reduce opioid craving, and control mood and anxiety.

The findings indicate that while respondents primarily acquired prescribed gabapentin to control pain (81.5%), they tended to acquire both prescribed and non-prescribed gabapentin for a host of other reasons. However, unlike previous studies, no respondents in this sample reported using gabapentin to hurt themselves, and few used because they were addicted to gabapentin, to control alcohol withdrawal or increase effects of medications for OUD (e.g., Suboxone) effects. Although it is not surprising that most respondents had procured gabapentin to control mood or anxiety, 86.0% reported acquiring both prescribed and non-prescribed gabapentin for this reason. These findings may point to how readily available non-prescribed sources of gabapentin have become. Findings showing that one-third of the sample used prescribed gabapentin to help with opioid withdrawal and cravings may point to self-medicating with gabapentin and avoidance of formal treatment.

Persons with a history of overdose were more likely to have used gabapentin. However, it is not known if gabapentin, which might have enhanced overdose risk, was used at the time of an overdose. Studies have shown that concomitant use of opioids and gabapentin use is associated with increased likelihood for opioid-related fatalities (Gomes et al., 2017) and inpatient hospitalization (Peckham, Fairman, et al., 2018). Although the exact mechanism for the increased risk of overdose seen in concomitant opioid-gabapentin users is unknown, animal studies have indicated that pregabalin prevents morphine tolerance and at high doses causes respiratory depression (Hasanein & Shakeri, 2014). Gabapentin has also been shown to reduce opioid-induced hyperalgesia in animal models (Stoicea et al., 2015). In humans, gabapentin’s pain reduction benefits may increase the likelihood of co-use with opioids, producing increased overdose risk. Additionally, gabapentin was more likely to be used by persons currently injecting opioids, again marking a subgroup with perhaps greater OUD severity. Public health officials and clinicians must recognize the compelling evidence that concomitant gabapentin-opioid is dangerous. Future research that examines the relationship between gabapentin dosage and frequency of co-occurring gabapentin-opioid use with overdose risk is important to explicate gabapentin-related overdose risk

Although it was found that women were more likely to report ever using gabapentin than men, overall, the reasons for gabapentin use did not meaningfully differ by gender. It is important for future research to explore why women with OUD are more likely to use gabapentin.

This study contributes to the current literature by supporting the finding that persons with OUD seeking inpatient withdrawal management report misusing prescription medications like gabapentin at high rates (Wilens, Zulauf, Ryland, Carrellas, & Catalina-Wellington, 2015). It also extends the literature by identifying reasons for gabapentin use among persons with OUD. One previous study did explore patient-reported reasons for combining prescription substances, including gabapentin, but was limited by its small sample size of twenty-nine individuals (Chatterjee et al., 2019). Moreover, the current study also identifies differences in these reasons between those who have been prescribed gabapentin and those who have used it without a prescription.

4.1. Limitations

This study has several limitations. First, it was conducted at a single site with primarily White and Hispanic participants. Therefore, these findings may not be representative of OUD patients, both in terms of racial-ethnic diversity and geography. Studies show that opioid type and potency may vary by location, which could contribute to the reasoning and frequency behind gabapentin-opioid co-use (Keyes, Cerda, Brady, Havens, & Galea, 2014). Second, this study relied solely on self-report of gabapentin use; prescriptions were not confirmed and urine toxicologic analysis was not available to confirm use at the time of admission. Third, although participants were informed that their answers were unrelated to their treatment, those with current gabapentin prescriptions, or those hoping to be prescribed gabapentin, may have been less willing to admit concomitant misuse or to endorse non-therapeutic uses of the medication, such as using to potentiate opioids. Along these lines, while there was no incentive to under report concurrent misuse with opioids, self-report may represent an under-reporting. Fourth, the dosages of gabapentin routinely administered were also unexplored. Finally, participants prescribed gabapentin reported overlapping reasons for using. While it cannot be determined whether participants used gabapentin as prescribed, it seems at least some reasons for use were not known or intended by the provider.

4.2. Conclusion

The current study extends existing research showing that gabapentin is a medication with high abuse potential in populations with OUD. Among people with OUD entering inpatient detoxification, we found high rates of history of gabapentin use, particularly non-prescribed gabapentin use. Therefore, explicating predictors and reasons for gabapentin misuse provides important implications for targeted screening and intervention efforts. Toxicologic screening of persons with concurrent OUD and gabapentin use may be warranted. Moreover, patients with OUD with comorbid pain should be routinely screened for gabapentin use/misuse given its high prevalence in this population, and attention to the treatment of pain is crucial.

Highlights.

  1. Education, injection drug use, overdose, and chronic pain correlated with gabapentin use (65.8%).

  2. Gabapentin acquisition was categorized as non-prescribed (47%), prescribed (21%) or both (33%).

  3. Gabapentin was primarily prescribed to control pain (81.5%).

  4. Non-prescribed GABA was used to get high or to substitute for or withdraw from opioids.

Acknowledgments

Role of Funding Sources

This study was funded by the National Institute on Drug Abuse (RO1 DA034261). Trial registered at clinicaltrials.gov; Clinical Trial # . Dr. Kenney’s contribution to this article was supported by grant number R34 AA026032 from the National Institute on Alcohol Abuse and Alcoholism at the National Institutes of Health.

Footnotes

Conflict of Interest

Dr. Bailey reports personal fees from BioDelivery Science International, Inc., grants, personal fees and other from Braeburn Pharmaceuticals, Inc., personal fees from Camurus AB, grants from Orexo, grants and other from Reckitt-Benckiser (Indivior), other from Titan Pharmaceuticals, Inc., outside the submitted work. (ICMJE form available upon request.)

Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

References

  1. Baird CR, Fox P, & Colvin LA (2014). Gabapentinoid abuse in order to potentiate the effect of methadone: a survey among substance misusers. Eur Addict Res, 20(3), 115–118. doi: 10.1159/000355268 [DOI] [PubMed] [Google Scholar]
  2. Barrueto F Jr., Green J, Howland MA, Hoffman RS, & Nelson LS (2002). Gabapentin withdrawal presenting as status epilepticus. J Toxicol Clin Toxicol, 40(7), 925–928. [DOI] [PubMed] [Google Scholar]
  3. Bastiaens L, Galus J, & Mazur C (2016). Abuse of Gabapentin is Associated with Opioid Addiction. Psychiatr Q, 87(4), 763–767. doi: 10.1007/s11126-016-9421-7 [DOI] [PubMed] [Google Scholar]
  4. Buttram ME, Kurtz SP, Dart RC, & Margolin ZR (2017). Law enforcement-derived data on gabapentin diversion and misuse, 2002–2015: diversion rates and qualitative research findings. Pharmacoepidemiol Drug Saf, 26(9), 1083–1086. doi: 10.1002/pds.4230 [DOI] [PubMed] [Google Scholar]
  5. Chatterjee A, Lopez D, Ramkellawan S, Brown R, Smith K, Gaeta JM, & Baggett TP (2019). “That’s what we call the cocktail”: Non-Opioid medication and supplement misuse among opioid users. Subst Abus, 1–8. doi: 10.1080/08897077.2019.1671943 [DOI] [PubMed] [Google Scholar]
  6. Dahlhamer J, Lucas J, Zelaya C, Nahin R, Mackey S, DeBar L, … Helmick C. (2018). Prevalence of Chronic Pain and High-Impact Chronic Pain Among Adults — United States, 2016. Morbidity and Mortality Weekly Report (MMWR), 67(36), 1001–1006. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Evoy KE, Morrison MD, & Saklad SR (2017). Abuse and Misuse of Pregabalin and Gabapentin. Drugs, 77(4), 403–426. doi: 10.1007/s40265-017-0700-x [DOI] [PubMed] [Google Scholar]
  8. Fukada C, Kohler JC, Boon H, Austin Z, & Krahn M (2012). Prescribing gabapentin off label: Perspectives from psychiatry, pain and neurology specialists. Can Pharm J (Ott), 145(6), 280–284 e281. doi: 10.3821/145.6.cpj280 [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Gomes T, Juurlink DN, Antoniou T, Mamdani MM, Paterson JM, & van den Brink W (2017). Gabapentin, opioids, and the risk of opioid-related death: A population-based nested case-control study. PLoS Med, 14(10), e1002396. doi: 10.1371/journal.pmed.1002396 [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hakkinen M, Vuori E, Kalso E, Gergov M, & Ojanpera I (2014). Profiles of pregabalin and gabapentin abuse by postmortem toxicology. Forensic Sci Int, 241, 1–6. doi: 10.1016/j.forsciint.2014.04.028 [DOI] [PubMed] [Google Scholar]
  11. Hasanein P, & Shakeri S (2014). Pregabalin role in inhibition of morphine analgesic tolerance and physical dependency in rats. Eur J Pharmacol, 742, 113–117. doi: 10.1016/j.ejphar.2014.08.030 [DOI] [PubMed] [Google Scholar]
  12. Keyes KM, Cerda M, Brady JE, Havens JR, & Galea S (2014). Understanding the rural-urban differences in nonmedical prescription opioid use and abuse in the United States. Am J Public Health, 104(2), e52–59. doi: 10.2105/AJPH.2013.301709 [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Klein-Schwartz W, Shepherd JG, Gorman S, & Dahl B (2003). Characterization of gabapentin overdose using a poison center case series. J Toxicol Clin Toxicol, 41(1), 11–15. [DOI] [PubMed] [Google Scholar]
  14. Kruszewski SP, Paczynski RP, & Kahn DA (2009). Gabapentin-induced delirium and dependence. J Psychiatr Pract, 15(4), 314–319. doi: 10.1097/01.pra.0000358318.73684.df [DOI] [PubMed] [Google Scholar]
  15. Lyndon A, Audrey S, Wells C, Burnell ES, Ingle S, Hill R, … Henderson G. (2017). Risk to heroin users of polydrug use of pregabalin or gabapentin. Addiction, 112(9), 1580–1589. doi: 10.1111/add.13843 [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Moore RA, Wiffen PJ, Derry S, Toelle T, & Rice AS (2014). Gabapentin for chronic neuropathic pain and fibromyalgia in adults. Cochrane Database Syst Rev(4), CD007938. doi: 10.1002/14651858.CD007938.pub3 [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Pauly N, Slavova S, Freeman P, Lofwall MR, & Talbert J (2017). Investogating gabapentin as a drug of abuse: Associations between gabapentin prescribing, substance use disorders and opioid-related poisonings. Paper presented at the Addiction Health Services Research Conference, Madison, WI. [Google Scholar]
  18. Peckham AM, Ananickal MJ, & Sclar DA (2018). Gabapentin use, abuse, and the US opioid epidemic: the case for reclassification as a controlled substance and the need for pharmacovigilance. Risk Manag Healthc Policy, 11, 109–116. doi: 10.2147/RMHP.S168504 [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Peckham AM, Evoy KE, Covvey JR, Ochs L, Fairman KA, & Sclar DA (2018). Predictors of Gabapentin Overuse With or Without Concomitant Opioids in a Commercially Insured U.S. Population. Pharmacotherapy, 38(4), 436–443. doi: 10.1002/phar.2096 [DOI] [PubMed] [Google Scholar]
  20. Peckham AM, Evoy KE, Ochs L, & Covvey JR (2018). Gabapentin for Off-Label Use: Evidence-Based or Cause for Concern? Subst Abuse, 12, 1178221818801311. doi: 10.1177/1178221818801311 [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Peckham AM, Fairman KA, & Sclar DA (2018). All-Cause and Drug-Related Medical Events Associated with Overuse of Gabapentin and/or Opioid Medications: A Retrospective Cohort Analysis of a Commercially Insured US Population. Drug Saf, 41(2), 213–228. doi: 10.1007/s40264-017-0595-1 [DOI] [PubMed] [Google Scholar]
  22. Peterson BL (2009). Prevalence of gabapentin in impaired driving cases in Washington State in 2003–2007. J Anal Toxicol, 33(8), 545–549. doi: 10.1093/jat/33.8.545 [DOI] [PubMed] [Google Scholar]
  23. Quintiles IMS Institute. (2019). Medicines use and spending in the U.S.: a review of 2016 and outlook to 2021. Retrieved from Parsippany, NJ: https://www.iqvia.com/insights/the-iqvia-institute/reports/medicine-use-and-spending-in-the-us-a-review-of-2018-and-outlook-to-2023 [Google Scholar]
  24. Reeves RR, & Ladner ME (2014). Potentiation of the effect of buprenorphine/naloxone with gabapentin or quetiapine. Am J Psychiatry, 171(6), 691. doi: 10.1176/appi.ajp.2014.13111526 [DOI] [PubMed] [Google Scholar]
  25. Slavova S, Miller A, Bunn TL, White JR, Kirschke D, Light T, … Winecker R. (2018). Prevalence of gabapentin in drug overdose postmortem toxicology testing results. Drug Alcohol Depend, 186, 80–85. doi: 10.1016/j.drugalcdep.2018.01.018 [DOI] [PubMed] [Google Scholar]
  26. Smith RV, Havens JR, & Walsh SL (2016). Gabapentin misuse, abuse and diversion: a systematic review. Addiction, 111(7), 1160–1174. doi: 10.1111/add.13324 [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Smith RV, Lofwall MR, & Havens JR (2015). Abuse and diversion of gabapentin among nonmedical prescription opioid users in Appalachian Kentucky. Am J Psychiatry, 172(5), 487–488. doi: 10.1176/appi.ajp.2014.14101272 [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Stoicea N, Russell D, Weidner G, Durda M, Joseph NC, Yu J, & Bergese SD (2015). Opioid-induced hyperalgesia in chronic pain patients and the mitigating effects of gabapentin. Front Pharmacol, 6, 104. doi: 10.3389/fphar.2015.00104 [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Throckmorton DC, Gottlieb S, & Woodcock J (2018). The FDA and the Next Wave of Drug Abuse - Proactive Pharmacovigilance. N Engl J Med, 379(3), 205–207. doi: 10.1056/NEJMp1806486 [DOI] [PubMed] [Google Scholar]
  30. Throckmorton DC, & Woodcock J (2018). Combined Gabapentinoid and Opioid Use: The Consequences of Shifting Prescribing Trends. Ann Intern Med, 169(10), 727–728. doi: 10.7326/M18-2175 [DOI] [PubMed] [Google Scholar]
  31. Victorri-Vigneau C, Guerlais M, & Jolliet P (2007). Abuse, dependency and withdrawal with gabapentin: a first case report. Pharmacopsychiatry, 40(1), 43–44. doi: 10.1055/s-2006-958522 [DOI] [PubMed] [Google Scholar]
  32. Wilens T, Zulauf C, Ryland D, Carrellas N, & Catalina-Wellington I (2015). Prescription medication misuse among opioid dependent patients seeking inpatient detoxification. Am J Addict, 24(2), 173–177. doi: 10.1111/ajad.12159 [DOI] [PubMed] [Google Scholar]
  33. Wills B, Reynolds P, Chu E, Murphy C, Cumpston K, Stromberg P, & Rose R (2014). Clinical outcomes in newer anticonvulsant overdose: a poison center observational study. J Med Toxicol, 10(3), 254–260. doi: 10.1007/s13181-014-0384-5 [DOI] [PMC free article] [PubMed] [Google Scholar]

RESOURCES