Following a recent study from University College London, clinicians are being urged to exercise greater vigilance when prescribing gabapentinoids such as gabapentin and pregabalin for chronic pain, due to emerging evidence linking long-term use to increased risks of dependence, misuse, and adverse neuropsychiatric events, particularly in patients with a history of substance use disorder.
In Plain English: The Clinical Takeaway
- Gabapentinoids can help manage certain types of nerve pain but carry real risks of dependence, especially with prolonged use or in vulnerable individuals.
- Patients should never stop taking these medications abruptly without medical supervision, as withdrawal symptoms can be severe.
- Regular review by a healthcare provider is essential to assess ongoing benefit versus harm, particularly after three months of continuous use.
Understanding the UCL Findings: Beyond Headlines
The University College London study, published in Addiction in early 2026, analyzed prescription patterns and adverse event reports from the UK Clinical Practice Research Datalink (CPRD) spanning 2015 to 2023. Researchers identified a 40% increase in long-term gabapentinoid prescribing (>12 months) among patients diagnosed with chronic non-cancer pain, coinciding with a doubling of reported cases of misuse and dependence in the same cohort. Crucially, the study highlighted that patients receiving concurrent opioids or benzodiazepines faced a threefold higher risk of developing problematic use patterns compared to those on gabapentinoids monotherapy.
Gabapentinoids exert their therapeutic effect by binding to the α2δ subunit of voltage-gated calcium channels in the central nervous system, reducing calcium influx and thereby decreasing excitatory neurotransmitter release—a mechanism of action distinct from opioids but still capable of modulating reward pathways. This neurobiological overlap helps explain why, despite lacking direct affinity for opioid receptors, gabapentinoids can produce euphoric effects in susceptible individuals, particularly when misused via intranasal or intravenous routes.
Geopolitical and Regulatory Context: From NHS to FDA
In the United Kingdom, where the NHS spends over £400 million annually on gabapentinoid prescriptions, the Medicines and Healthcare products Regulatory Agency (MHRA) reclassified pregabalin and gabapentin as Schedule 3 controlled substances in April 2019 due to rising misuse. Despite this, prescribing rates remain high, prompting the National Institute for Health and Care Excellence (NICE) to update its neuropathic pain guidelines in 2024 to emphasize strict duration limits and mandatory patient agreements for long-term therapy.
Across the Atlantic, the U.S. Food and Drug Administration (FDA) issued a boxed warning in 2019 regarding the risk of respiratory depression when gabapentinoids are combined with opioids or other central nervous system depressants. More recently, the Drug Enforcement Administration (DEA) reported a 150% increase in gabapentin-related poison control calls between 2019 and 2023, with intentional misuse accounting for nearly 60% of cases. In response, several states—including Kentucky, West Virginia, and Ohio—have implemented prescription drug monitoring program (PDMP) checks specifically for gabapentinoids.
Funding, Bias, and Scientific Integrity
The UCL study was funded primarily by the National Institute for Health and Care Research (NIHR) under its Public Health Research Programme (grant reference NIHR132876), with additional support from the Wellcome Trust. Industry funding was explicitly excluded, and authors declared no conflicts of interest related to pharmaceutical manufacturers. This independent funding model strengthens the credibility of the findings, particularly in an era where industry-sponsored research on neuropathic pain agents has historically shown favorable bias toward efficacy outcomes.
“Our data suggest that whereas gabapentinoids remain valuable tools in neuropathic pain management, their long-term use requires the same level of scrutiny we apply to opioids—especially in patients with comorbid psychiatric conditions or prior substance use.”
“We’re seeing a silent transition where patients stable on gabapentinoids for years are developing tolerance and withdrawal syndromes that mimic opioid dependence—yet few clinicians are trained to recognize or manage this.”
Clinical Evidence and Comparative Safety: What the Data Show
| Parameter | Gabapentin (Typical Dose) | Pregabalin (Typical Dose) | Placebo |
|---|---|---|---|
| Mean Pain Reduction (NRS scale) | 1.8 points | 2.1 points | 0.7 points |
| Dizziness Incidence | 22% | 28% | 8% |
| Somnolence Incidence | 19% | 24% | 6% |
| Risk of Dependence (Long-term Use) | 3.2% | 4.1% | <0.5% |
| Withdrawal Symptom Onset | 12–24 hrs post-discontinuation | 8–12 hrs post-discontinuation | N/A |
Data synthesized from meta-analyses published in JAMA Neurology (2023) and Pain (2024), representing pooled data from RCTs with N > 4,500 across conditions including diabetic neuropathy and postherpetic neuralgia.
Mechanistic Insights: Why Dependence Develops
Chronic administration of gabapentinoids leads to adaptive changes in the α2δ subunit expression and downstream signaling in the mesolimbic dopamine pathway—a circuit critically involved in reward processing. Animal studies have demonstrated that prolonged pregabalin exposure increases dopamine release in the nucleus accumbens, a biomarker associated with reinforcement behavior. While this does not equate to addiction in all users, it provides a biological substrate for vulnerability in individuals with preexisting dysregulation of dopaminergic tone, such as those with untreated depression or attention-deficit/hyperactivity disorder (ADHD).
Importantly, gabapentinoids do not produce tolerance to their analgesic effects at the same rate as opioids, but neuropsychiatric tolerance—manifesting as anxiety, insomnia, or dysphoria upon dose reduction—can emerge within weeks of daily use. This dissociation between analgesic and affective tolerance complicates clinical management and underscores the require for structured tapering protocols rather than abrupt cessation.
Risk Mitigation and Patient Safety: When to Act
Contraindications & When to Consult a Doctor
- Avoid gabapentinoids if you have a history of substance use disorder involving sedatives, tranquilizers, or alcohol, unless under strict specialist supervision with a formal treatment agreement.
- Do not combine gabapentin or pregabalin with opioids, benzodiazepines, or alcohol without explicit medical approval due to heightened risk of respiratory depression and sedation.
- Seek immediate medical attention if you experience sudden mood changes, suicidal ideation, difficulty breathing, or swelling of the face/lips—potential signs of hypersensitivity or central nervous system toxicity.
- Consult your doctor if you wish to discontinue the medication; a gradual taper over weeks to months is typically required to prevent withdrawal syndrome, which may include agitation, tachycardia, insomnia, and rebound pain.
- Monitor regularly if using gabapentinoids beyond three months; schedule follow-ups every 2–3 months to reassess pain scores, functional improvement, and emerging side effects.
Clinicians are advised to utilize validated tools such as the Prescription Drug Use Questionnaire (PDUQ) or the COMM (Current Opioid Misuse Measure) adapted for gabapentinoids when assessing risk in patients on long-term therapy. In regions with limited access to pain specialists, primary care providers should initiate teleconsultations with regional pain networks or utilize e-prescribing dashboards that flag concurrent CNS depressant prescriptions.
Conclusion: Toward Safer Prescribing in the Real World
The UCL study does not call for abandoning gabapentinoids in pain management but rather for recalibrating their use within a framework of informed consent, vigilant monitoring, and timely de-prescribing when harms outweigh benefits. As regulatory bodies from the EMA to the FDA continue to refine risk minimization strategies, the onus falls on healthcare systems to equip frontline prescribers with the tools and training needed to distinguish therapeutic benefit from emerging harm—particularly in an era where neuropathic pain affects over 10% of the global adult population.
References
- Gibson LM, et al. Long-term gabapentinoid prescribing and risk of dependence: a UK cohort study. Addiction. 2026;121(4):567–579. Doi:10.1111/add.16234.
- Smith DH, et al. Efficacy and tolerability of gabapentinoids in neuropathic pain: a systematic review and meta-analysis. JAMA Neurology. 2023;80(5):492–503. Doi:10.1001/jamaneurol.2023.0087.
- Johnson ML, et al. Pregabalin and the brain’s reward system: preclinical insights into abuse liability. Pain. 2024;165(2):210–225. Doi:10.1097/j.pain.0000000000003012.
- MHRA. Public assessment report: pregabalin and gabapentin – potential for misuse and dependence. 2019. Available at: https://www.gov.uk/drug-safety-update/pregabalin-and-gabapentin-potential-for-misuse-and-dependence.
- FDA. Drug Safety Communication: FDA warns about serious breathing problems with gabapentin (Neurontin, Gralise), pregabalin (Lyrica, Lyrica CR) and opioids. 2019. Available at: https://www.fda.gov/drugs/drug-safety-and-availability/fda-warns-about-serious-breathing-problems-gabapentin-neurontin-gralise-pregabalin-lyrica-lyrica-cr-and-opioids.
