Gabapentin has not been proven to cause dementia, but a growing body of observational research links long-term use to a modestly higher risk of cognitive decline, and the question is far from settled. A 2025 meta-analysis pooling data from over 325,000 participants found that people who used gabapentinoids had roughly 28% higher odds of developing Alzheimer’s-type dementia compared to non-users, though that figure weakened when the analysis was limited to higher-quality studies. The honest picture is more complicated than a yes-or-no, because the people who take gabapentin tend to have chronic pain, sleep problems, and other conditions that themselves raise dementia risk.
How Gabapentin Works in the Brain
Gabapentin was originally developed as an anti-seizure drug and is now prescribed far more often for nerve pain, restless legs, and a grab bag of off-label conditions. It works by binding to a specific protein on nerve cells called the alpha-2-delta-1 subunit of voltage-sensitive calcium channels.1PubMed. Mechanisms of action of gabapentin By latching onto that site, gabapentin reduces calcium flow into certain nerve terminals, which in turn dials down the release of excitatory chemical signals. In the hippocampus and neocortex, this can reduce the strength of synaptic transmission by roughly 30 to 40%.2European Journal of Pharmacology. Gabapentin inhibits presynaptic Ca2+ influx and synaptic transmission in rat hippocampus and neocortex
That same alpha-2-delta-1 protein turns out to play a second, unexpected role: it is the receptor through which certain brain proteins called thrombospondins promote the formation of new excitatory synapses. Gabapentin blocks thrombospondin from docking at this site and powerfully inhibits the creation of new synaptic connections, both in cell cultures and in living animals.3PubMed Central. Gabapentin receptor alpha2delta-1 is a neuronal thrombospondin receptor responsible for excitatory CNS synaptogenesis Importantly, this effect appears to be specific to new synapse formation. Research in pain models has shown that gabapentin prevents the establishment of new pain-related synapses but does not dismantle synapses that already exist.4PubMed Central. Gabapentin prevents synaptogenesis between sensory and spinal cord neurons induced by thrombospondin-4 acting on pre-synaptic Cav α2δ1 subunits and involving T-type Ca2+ channels Whether chronic suppression of new synapse formation over years could starve the brain of the ongoing synaptic remodeling it needs to maintain memory and learning is the biological question at the heart of the dementia concern. Nobody has definitively answered it yet in humans.
What the Population Studies Show
Several large observational studies have now looked at whether people who take gabapentin develop dementia at higher rates. The findings consistently point in the same direction, though they disagree on how strong the signal is.
A 2025 study of chronic low back pain patients found that those with six or more gabapentin prescriptions had about a 29% higher rate of dementia and an 85% higher rate of mild cognitive impairment compared to patients not prescribed gabapentin. The risk climbed further with more prescriptions: patients with twelve or more fills had a 40% higher dementia rate.5PubMed. Risk of dementia following gabapentin prescription in chronic low back pain patients An earlier Taiwanese study using national insurance records also found a dose-dependent pattern, with risk rising alongside cumulative doses. That study reported a striking hazard ratio for patients under 50, who had roughly three times the dementia risk of unexposed peers, though the absolute number of dementia cases in younger people was small.6PubMed Central. The association between Gabapentin or Pregabalin use and the risk of dementia: an analysis of the National Health Insurance Research Database in Taiwan
A 2026 meta-analysis that pooled five observational studies, covering over 325,000 participants, found that gabapentinoid use was associated with about 28% higher odds of Alzheimer’s-type dementia. But when the authors restricted the analysis to studies judged to have a low risk of bias, the association shrank and was no longer statistically significant.7PubMed. Gabapentinoid Use and Risk of Alzheimer’s Disease-Related Dementias: A Systematic Review and Meta-analysis of Observational Studies That finding is a caution flag: the link might be real, or it might partly reflect problems with the studies themselves.
Not every study agrees that more gabapentin means more risk. A nested case-control study from the UK that matched gabapentin users with chronic pain controls found no significant difference in dementia risk between low and high cumulative doses of the drug, and the overall adjusted risk was close to neutral.8PubMed. Association between gabapentin use and risk of dementia in adults with chronic pain: A nested case-control study The contradiction between this study and the Taiwanese and American data is unresolved and highlights how much the answer depends on study design, population, and what you compare gabapentin users against.
Why These Studies Cannot Prove Causation
Every study cited above is observational. Nobody randomized a group of healthy people to take gabapentin for a decade and then checked whether they developed dementia. That kind of trial would be ethically impossible and logistically absurd, which means the evidence we have is inherently limited.
The core problem is confounding by indication. People prescribed gabapentin typically have chronic pain, neuropathy, or epilepsy. Chronic pain alone is an independent risk factor for cognitive decline, likely through sleep disruption, reduced physical activity, and the neuroinflammation that accompanies long-term pain states. If gabapentin users develop more dementia, that could be the gabapentin, the underlying pain, or both. The 2025 back-pain study tried to address this by comparing gabapentin users only to other chronic low back pain patients, but even within that group, patients who end up on gabapentin may have more severe or treatment-resistant pain, worse sleep, or more comorbidities.5PubMed. Risk of dementia following gabapentin prescription in chronic low back pain patients
Reverse causality is another concern. The earliest, subtlest stages of dementia can produce symptoms like neuropathic sensations, poor balance, and disrupted sleep, any of which could lead a doctor to prescribe gabapentin. In that scenario, gabapentin use does not cause cognitive decline; it is prescribed because cognitive decline has already quietly begun. Studies that find a stronger association in younger patients have been interpreted both ways: either gabapentin is more dangerous to younger brains, or early-onset dementia is more likely to prompt gabapentin prescriptions before anyone suspects cognitive trouble.
Short-Term Cognitive Side Effects
Even setting aside the long-term dementia question, gabapentin clearly causes short-term cognitive fog in some people. A study tracking older adults who were cognitively normal at baseline found that starting gabapentin was associated with roughly 55% higher odds of measurable cognitive decline at the next assessment visit.9PubMed Central. The association of gabapentin initiation and neurocognitive changes in older adults with normal cognition A smaller study in people with spinal cord injuries documented declines in memory, executive function, and attention within one week of starting the drug. Interestingly, scores partially recovered by the four-week mark in several domains, suggesting the brain adapts somewhat with continued use.10Spinal Cord Series and Cases. Adverse cognitive effect of gabapentin in individuals with spinal cord injury: preliminary findings
These short-term effects matter for two reasons. First, in older adults, the foggy thinking gabapentin causes can be mistaken for early dementia and lead to unnecessary testing or medication changes. Second, even temporary cognitive blunting raises fall risk and impairs daily functioning, which can set off a cascade of problems, especially in frail older people. Whether years of this low-grade cognitive suppression accumulates into something that resembles or accelerates dementia is exactly the unanswered question researchers are circling.
Does Cognitive Function Bounce Back After Stopping?
Some evidence suggests it does. A self-controlled study that tracked patients before, during, and after gabapentin use found that cognitive symptom rates were higher while people were taking gabapentin (particularly when combined with a common blood-pressure medication) and dropped after they stopped. In adults 65 and older, the rate of cognitive symptoms was roughly 74% higher during use than after discontinuation.11medRxiv. Do Cognitive Symptoms Improve When Gabapentin and Dihydropyridine Calcium Channel Blocker Therapy Are Stopped? A Self-Controlled Case Series That pattern is reassuring: it suggests at least some of gabapentin’s cognitive toll is a pharmacological effect that lifts when the drug clears rather than a sign of permanent brain damage.
But stopping gabapentin is not always straightforward. Abrupt discontinuation after long-term use can trigger its own neurological crisis, a rebound of excitatory brain signaling sometimes described as a “glutamate storm.” A case report of a 94-year-old woman who was suddenly taken off gabapentinoids described severe hyperactive delirium from withdrawal-induced neurotoxicity.12PubMed Central. The Hidden Dangers of Gabapentinoids in Older Adults: From Accelerated Cognitive Decline to Withdrawal-Induced Neurotoxicity The recommended approach is a very gradual taper, but that adds weeks or months during which the cognitive effects continue. For someone already concerned about their memory, this puts them in a difficult spot: staying on the drug carries theoretical long-term risk, but quitting too fast carries immediate danger.
Kidney Function and Gabapentin Buildup
Gabapentin is not processed by the liver. It passes through the body and is eliminated almost entirely by the kidneys. In someone with healthy kidney function, the drug clears fairly quickly, and toxic levels rarely build up.13PubMed Central. Myoclonus in renal failure: Two cases of gabapentin toxicity But kidney function declines with age, often without obvious symptoms, and when the kidneys slow down, gabapentin concentrations in the blood can rise to dangerous levels.
Gabapentin toxicity from impaired kidneys can produce altered mental status, confusion, and neurological symptoms that look a lot like dementia. A case report from the Mayo Clinic described progressive kidney failure as a “frequently underrecognized” risk factor for gabapentin toxicity.14Mayo Clinic Proceedings. A 71-Year-Old Man With Altered Mental Status A broader review found that elderly individuals with multiple health conditions were overrepresented among those experiencing toxic effects, and many had received gabapentin doses that were inappropriately high for their level of kidney function.15American Journal of Medicine. Gabapentin Toxicity in Patients with Chronic Kidney Disease: A Preventable Cause of Morbidity
This matters to the dementia question because some portion of the cognitive problems attributed to gabapentin in older adults may actually be preventable toxicity from poor dose adjustment. If your kidney function has not been checked recently and you are on gabapentin, the drug level in your blood could be significantly higher than your prescriber intended. Asking for a simple blood test to check kidney function is one of the most practical steps you can take.
How Gabapentin Compares to Pregabalin
Pregabalin is gabapentin’s chemical cousin and works through the same alpha-2-delta-1 calcium channel target. The two drugs are often discussed interchangeably under the umbrella term “gabapentinoids,” but their cognitive profiles may differ. In an animal study that directly compared gabapentin, pregabalin, and baclofen, chronic pregabalin significantly impaired object recognition memory, while gabapentin alone did not. However, when gabapentin was combined with other drugs, cognitive impairment emerged.16PubMed Central. Comparative effects of chronic administrations of gabapentin, pregabalin and baclofen on rat memory using object recognition test
A meta-analysis that looked at both clinical and animal studies found that gabapentin given to healthy animals actually appeared to improve memory in some paradigms, depending on the timing of administration, while pregabalin did not show that effect.17PubMed Central. The effect of gabapentin and pregabalin administration on memory in clinical and preclinical studies: a meta-analysis and systematic review These are animal results and should not be over-interpreted, but they raise the possibility that gabapentin and pregabalin carry different cognitive risks. Most of the large population studies do not distinguish clearly between the two drugs, which muddies the picture for people trying to decide which one to take.
The Polypharmacy Problem
In practice, gabapentin is rarely the only drug affecting someone’s brain. A study of medication patterns among people living with dementia found that the most common central-nervous-system drug combination was opioids plus antidepressants plus gabapentin.18PubMed Central. Central Nervous System Polypharmacy Among People Living With Dementia Each of those drugs has its own sedating and cognition-dulling effects, and the combination is likely worse than any single one. Gabapentinoids combined with opioids carry additional warnings due to the risk of sedation and respiratory depression, a concern that led to stronger cautions in geriatric prescribing guidelines.
When population studies find that gabapentin users develop more cognitive problems, they are rarely capturing the effect of gabapentin in isolation. They are capturing the effect of gabapentin in people who also take opioids, sleep aids, antidepressants, and blood-pressure medications, many of which independently affect the brain. Teasing apart gabapentin’s individual contribution is extremely difficult with the study designs currently available.
Rising Prescriptions and Off-Label Use
Gabapentinoid prescribing among older adults has risen sharply in recent years, partly because opioid prescribing has been curtailed. A retrospective study at a geriatric falls clinic found that gabapentinoid use climbed from about 3.5% of patients in 2013-14 to 15% by 2023, while opioid use dropped from 29% to 12% over the same period.19PubMed Central. Trends and Guideline Adherence in Gabapentinoid Use among Geriatric Outpatients: A Retrospective Cross-Sectional Study at a Falls Clinic That fourfold increase reflects a broader trend: as doctors moved away from opioids for chronic pain management, gabapentin absorbed much of the demand.
The same study found that among patients prescribed gabapentinoids for pain, only about 7% had a condition for which national guidelines clearly supported the drug’s use. Roughly 62% had it prescribed for conditions where the evidence was insufficient.19PubMed Central. Trends and Guideline Adherence in Gabapentinoid Use among Geriatric Outpatients: A Retrospective Cross-Sectional Study at a Falls Clinic The scale of off-label prescribing matters because it means many older adults are accepting the cognitive risks of gabapentin for conditions where the drug may not even be helping much. If you are taking gabapentin for general aches or non-specific pain rather than a well-established neuropathic condition, the risk-benefit calculation tips further toward caution.
When Gabapentin Is Used for People Who Already Have Dementia
In an ironic twist, gabapentin is sometimes prescribed to manage behavioral symptoms in people who already have dementia, particularly agitation, aggression, and nighttime restlessness. A systematic review found preliminary low-grade evidence that gabapentin and pregabalin may help with these symptoms in Alzheimer’s disease, though no controlled trials have been published. The review positioned gabapentinoids as a last-resort option after better-studied medications have failed or carry unacceptable risks.20PubMed Central. Gabapentin and pregabalin to treat aggressivity in dementia: a systematic review and illustrative case report Individual case reports have described meaningful improvement in nocturnal agitation with low-dose gabapentin.21PubMed Central. Gabapentin in the treatment of dementia-associated nocturnal agitation
A broader evidence review noted that while most published cases reported gabapentin as well-tolerated and effective for behavioral symptoms, two case reports questioned its appropriateness in dementia with Lewy bodies specifically, where it appeared to worsen agitation.22PubMed. Use of gabapentin in the treatment of behavioural and psychological symptoms of dementia: a review of the evidence The evidence base here consists entirely of case reports and small case series, so it should be treated as hypothesis-generating rather than conclusive. Still, the fact that gabapentin is simultaneously suspected of hastening dementia and used to treat its symptoms underscores how poorly understood its long-term brain effects remain.
What to Do If You Are Taking Gabapentin
If you are currently on gabapentin and worried about dementia, the worst thing you can do is stop the drug abruptly, as discussed earlier regarding withdrawal risks. The evidence does not support panic. The observed association with dementia is modest in well-designed studies and may be partly or entirely explained by confounding. No study has established that gabapentin causes the kind of brain damage seen in Alzheimer’s disease.
That said, several practical steps can reduce your risk of cognitive side effects. Ask your doctor whether your kidney function has been checked recently, since impaired clearance is a preventable cause of toxicity. Review whether you are taking gabapentin for a condition that actually responds well to it, since the off-label prescribing data suggests a majority of older adults may not be. If you and your doctor decide to stop, plan a gradual taper over weeks rather than days. And if you are on multiple brain-active medications, ask whether any can be reduced or eliminated. The combination is often more dangerous than any single drug.
Researchers recognize that randomized trials specifically designed to answer the causation question are unlikely to happen. The best evidence in the pipeline will probably come from larger and better-designed observational studies that more carefully control for chronic pain, sleep disorders, and other confounders, alongside self-controlled designs that compare periods on and off the drug within the same individuals. Until that evidence arrives, gabapentin sits in an uncomfortable middle ground: widely prescribed, probably safe for most people at appropriate doses over limited periods, but carrying genuine uncertainty about what decades of use might do to an aging brain.