Gabapentin can cause anger, irritability, and other mood changes in a subset of people who take it, though this is not among its most frequently reported side effects. The strongest evidence links these reactions to specific populations, particularly children with neurological conditions and adults with brain injuries or cognitive impairment. For most adults, gabapentin either has no meaningful effect on mood or modestly improves it, which is part of what makes the anger reports so confusing for people who experience them.
The Clearest Evidence Comes From Children
The most striking reports of gabapentin-related anger and aggression involve pediatric patients being treated for epilepsy. In the mid-1990s, several clinical teams independently documented children who developed severe behavioral problems after starting gabapentin. One report described seven children on gabapentin as add-on therapy who developed tantrums, aggression directed at others, hyperactivity, and defiance. These were not subtle shifts; parents rated the behavioral changes as their most troublesome concern. All the problems reversed when the drug was reduced or stopped.1PubMed. Behavioral side effects of gabapentin in children
A separate report described three children with learning disabilities and hard-to-control seizures who became hyperactive and had explosive outbursts with aggressive and oppositional behavior on gabapentin. The behavioral problems were bad enough that their doctors stopped the drug even though it was helping their seizures.2PubMed. Gabapentin toxicity in children manifesting as behavioral changes Another case report described two children with intractable seizures who developed aggressive behavior severe enough to require dose reduction or stopping the medication entirely, with the authors noting these reactions seemed more likely in children with intellectual disabilities.3PubMed. Gabapentin associated with aggressive behavior in pediatric patients with seizures
A consistent detail across these reports is that the children who developed the worst behavioral reactions tended to have pre-existing cognitive or developmental issues. This pattern matters because it points toward something about how the brain processes gabapentin differently when its baseline wiring is already atypical.
Adults With Brain Injuries Face Similar Risks
The pattern seen in children with neurological conditions carries over to adults with brain injuries. A case report documented two brain-injured patients who developed heightened anxiety and restlessness within one week of starting gabapentin at 900 mg daily. Both reported that their psychological symptoms improved within 48 hours of stopping the drug.4PubMed. Psychomotor agitation following gabapentin use in brain injury The researchers concluded that gabapentin may cause agitation specifically in people with cognitive impairment, and recommended close monitoring for restlessness and anxiety in this group.
The thread connecting children with learning disabilities and adults with brain injuries is pre-existing compromise to brain function. When the brain’s inhibitory and excitatory signaling is already disrupted, adding a drug that modulates those systems can sometimes tip the balance in an unexpected direction. This is sometimes called a paradoxical reaction, where a drug designed to calm neural activity instead causes agitation or irritability in certain individuals.
How Gabapentin Affects the Brain
Gabapentin works by binding to a specific part of voltage-gated calcium channels in the nervous system. Research has shown that it does not block these channels immediately. Instead, when taken over time, it reduces the number of calcium channel subunits that reach the cell surface, which effectively turns down the volume on certain types of nerve signaling.5PubMed Central. Pharmacological disruption of calcium channel trafficking by the alpha2delta ligand gabapentin This is why gabapentin takes days to weeks to reach its full effect and why behavioral changes can also develop gradually.
A review of psychiatric and behavioral side effects of anti-seizure medications found that several overlapping mechanisms can lead to mood and behavioral problems. These include excessive modulation of certain receptor systems, broad enhancement of inhibitory neurotransmission, and interactions between drugs.6PubMed. Psychiatric and behavioural side effects of antiseizure medications in epilepsy In other words, the same neural pathways that gabapentin targets for therapeutic benefit are the ones that can misfire and produce irritability or anger in susceptible individuals.
For Most Adults, Gabapentin Is Mood-Neutral or Mildly Helpful
The pediatric and brain-injury cases are alarming, but they represent a small and identifiable fraction of gabapentin users. When researchers have looked at mood effects in broader adult populations, the picture is quite different. A pooled analysis of adults with restless legs syndrome taking gabapentin enacarbil (a prodrug that converts to gabapentin in the body) found that treatment improved several mood measures, including total mood disturbance, depression, fatigue, and confusion, compared with placebo. Anger and hostility scores, however, did not change significantly in either direction.7PubMed. The Effect of Gabapentin Enacarbil on Quality of Life and Mood Outcomes in a Pooled Population of Adult Patients with Moderate-to-Severe Primary Restless Legs Syndrome That finding is worth sitting with: in a large group of adults, gabapentin made several dimensions of mood better and did not make anger worse.
Gabapentinoids as a class have also shown effectiveness for anxiety across a range of conditions. A systematic review and meta-analysis covering 42 randomized controlled trials found that gabapentin and pregabalin were more effective than placebo for disorders across the anxiety spectrum.8Molecular Psychiatry. Gabapentin and pregabalin in bipolar disorder, anxiety states, and insomnia: Systematic review, meta-analysis, and rationale Since anxiety and irritability often travel together, reducing anxiety can indirectly reduce anger in many people. This is part of why some patients report that gabapentin actually improves their mood and emotional regulation.
Interestingly, an animal study found that gabapentin reversed aggression, depression-like behavior, and anxiety in mice that had been socially isolated early in life, while having no behavioral effect on normally socialized mice.9PubMed. Protective effects of gabapentin against the seizure susceptibility and comorbid behavioral abnormalities in the early socially isolated mice That result echoes what clinicians see in humans: gabapentin’s mood effects depend heavily on the starting state of the person taking it.
The Bipolar Disorder Question
Gabapentin has been tried as a mood stabilizer for bipolar disorder, and the results are genuinely mixed in a way that matters for the anger question. An early open-label study reported that gabapentin was an effective add-on treatment for both the depressed and manic phases of bipolar illness.10Journal of Affective Disorders. Gabapentin as an adjunctive treatment in bipolar disorder But when the same idea was tested in a placebo-controlled trial, the placebo group actually improved more on mania scores than the gabapentin group did.11PubMed. Gabapentin in bipolar disorder: a placebo-controlled trial of adjunctive therapy
A separate double-blind preventive trial found that gabapentin did not cause emerging manic or depressive symptoms compared with placebo.12PubMed. A double-blind, randomized, placebo-controlled, prophylaxis study of adjunctive gabapentin for bipolar disorder So gabapentin probably does not reliably stabilize bipolar mood, but it also does not seem to destabilize it in the way you might fear if you only read the pediatric case reports. For people with bipolar disorder who are prescribed gabapentin for pain or another indication, the existing evidence does not suggest it will trigger mania or anger, though the controlled trial data is fairly thin.
Suicidality and Serious Mood Events
The FDA requires anti-seizure medications, including gabapentin, to carry a warning about increased risk of suicidal thoughts and behavior. The evidence behind this warning is complicated and somewhat contradictory for gabapentin specifically. A large study comparing suicide attempt rates before and after gabapentin prescriptions found no overall increase. In fact, for people with bipolar disorder, major depression, and other psychiatric conditions, suicide attempt rates actually went down after they started gabapentin.13PubMed Central. Gabapentin and Suicide Attempts
However, a large Swedish population study that compared the same individuals during periods when they were and were not taking gabapentinoids found a roughly 26% higher hazard for suicidal behavior and death from suicide during treatment periods. The same study found increased hazards for unintentional overdoses and injuries.14BMJ. Associations between gabapentinoids and suicidal behaviour, unintentional overdoses, injuries, road traffic incidents, and violent crime These two findings are not necessarily contradictory. The Swedish study included pregabalin alongside gabapentin, and the populations studied differ in important ways. The overall picture suggests that gabapentinoids may carry a modest risk of serious mood-related events in some individuals, even if the average effect across large groups is neutral or slightly beneficial.
Risk Factors That Make Mood Side Effects More Likely
Not everyone faces the same odds of developing anger or mood changes on gabapentin. Several factors have been identified that increase vulnerability:
- Age: Children are more susceptible to behavioral side effects than adults, as the pediatric literature consistently shows.
- Cognitive impairment: People with intellectual disabilities, brain injuries, or dementia appear to be at higher risk of paradoxical reactions.
- Kidney function: Gabapentin is eliminated almost entirely by the kidneys. In people with impaired kidney function, the drug can accumulate to toxic levels, causing confusion and other neuropsychiatric symptoms. In patients with healthy kidneys, toxicity is uncommon because the drug clears quickly.15PubMed Central. Myoclonus in renal failure: Two cases of gabapentin toxicity
- Dose: A retrospective study of over 110,000 older adults found that starting gabapentin at a higher dose was associated with a 29% higher risk of hospitalization for altered mental status compared with starting at a lower dose.16PubMed Central. Gabapentin dose and the 30-day risk of altered mental status in older adults
- Concurrent medications and substance use: A large UK primary care study found that people taking gabapentin alongside opioids, benzodiazepines, or antidepressants had higher rates of adverse outcomes. A history of mental health conditions or substance misuse also independently increased risk.17PubMed Central. Risk of adverse outcomes during gabapentinoid therapy and factors associated with increased risk in UK primary care using the clinical practice research datalink
The dose finding in older adults is particularly practical. Many of the problems people experience with gabapentin happen during initiation or dose increases, which is why standard practice is to start low and titrate slowly. If you are older, have any degree of kidney impairment, or take other central nervous system medications, a cautious starting dose is especially important.
Withdrawal Can Look Like the Drug Itself Caused the Problem
One underappreciated source of anger and agitation in gabapentin users is withdrawal. Gabapentin produces physical dependence faster than many people realize, and abrupt discontinuation can trigger serious symptoms. A case report described a patient who developed restlessness, confusion, agitation, and anxiety after gabapentin was stopped during a hospitalization. She was initially treated for alcohol withdrawal because the symptoms looked so similar, but benzodiazepines had no effect. The symptoms only resolved after gabapentin withdrawal was recognized as the cause.18American Journal of Health-System Pharmacy. Withdrawal symptoms after gabapentin discontinuation
This creates a tricky situation. Someone who wants to stop gabapentin because of mood changes may find that quitting abruptly makes the mood changes temporarily worse. The agitation from withdrawal can be mistaken for a continuation or worsening of the drug’s side effects. A scoping review of deprescribing strategies found that gabapentinoid use could be stopped successfully in at least a third of participants in randomized trials, but the process required structured dose-reduction protocols rather than abrupt cessation.19British Journal of Clinical Pharmacology. Deprescribing interventions for gabapentinoids in adults: A scoping review If you are experiencing mood changes and want to stop gabapentin, tapering over weeks under medical supervision is the standard approach.
How Gabapentin Compares With Pregabalin
People who develop mood side effects on gabapentin sometimes wonder whether switching to pregabalin would help. The two drugs work through the same basic mechanism and have similar side effect profiles overall. A systematic review and meta-analysis comparing the two for neuropathic pain found no significant differences in total adverse events, though gabapentin had a higher rate of nausea and vomiting.20Frontiers in Pain Research. Pregabalin vs. gabapentin in the treatment of neuropathic pain Neither drug came out clearly better or worse for psychiatric side effects in this comparison. Pregabalin is absorbed more predictably and reaches higher brain concentrations at equivalent doses, which could theoretically cut both ways: more reliable therapeutic effects but also more reliable side effects in susceptible individuals.
The Swedish population study mentioned earlier grouped gabapentin and pregabalin together and found similar patterns for both drugs regarding suicidal behavior and related outcomes.14BMJ. Associations between gabapentinoids and suicidal behaviour, unintentional overdoses, injuries, road traffic incidents, and violent crime So switching between the two is unlikely to solve a mood-related side effect, since the underlying pharmacology is so similar.
What People Report Online Versus What Clinical Trials Show
If you search for gabapentin and anger online, you will find a lot of alarming stories. A study that analyzed gabapentinoid-related posts on social media found a sharp divide between people sharing positive experiences and those voicing negative ones. Negative reports centered on ineffectiveness, withdrawal, and various side effects.21PubMed. Content and sentiment analysis of gabapentinoid-related tweets: An infodemiology study Self-reported experiences online tend to over-represent extreme outcomes in both directions. People who have neutral experiences on a medication rarely post about it, which skews the visible conversation toward dramatic reactions.
That said, dismissing patient reports would be a mistake. The pediatric aggression cases that eventually made it into the medical literature were first noticed by parents and caregivers, not by clinicians running trials. The clinical trial populations that show neutral or positive mood effects are carefully selected and tend to exclude people with the exact risk factors, like cognitive impairment or complex psychiatric histories, that make anger reactions more likely. Both the trial data and the patient reports contain genuine information; they just describe different subsets of gabapentin users.
Older Adults Deserve Extra Caution
Gabapentin is widely prescribed to older adults, particularly for nerve pain, and this population faces compounding risk factors for mood and cognitive side effects. Kidney function naturally declines with age, which means gabapentin clears from the body more slowly. Older adults are also more likely to take multiple medications that interact with gabapentin’s effects on the central nervous system. The study that found higher-dose gabapentin initiation increased the risk of altered mental status was conducted specifically in adults aged 65 and older, and the absolute risk, while small, was statistically robust across a large population.16PubMed Central. Gabapentin dose and the 30-day risk of altered mental status in older adults
Altered mental status in this context covers a range of symptoms from confusion and disorientation to agitation. A family member who notices a personality shift or increased irritability in an older relative who recently started or increased gabapentin should consider the medication as a possible factor, particularly if the person’s kidney function has not been checked recently or if they are on other sedating drugs.
When Gabapentin Is Not the Culprit
It is also worth acknowledging that not every mood change during gabapentin treatment is caused by gabapentin. The conditions it treats, including chronic pain, epilepsy, and anxiety, all have their own mood consequences. Chronic pain alone is strongly linked to irritability, depression, and anger. Poorly controlled seizures affect emotional regulation. If gabapentin is providing incomplete symptom relief, the underlying condition may be driving mood changes rather than the drug itself. Similarly, people prescribed gabapentin for one condition often have others; the UK primary care study found that concurrent mental health conditions were independently associated with a higher risk of all adverse outcomes during gabapentinoid therapy, regardless of the drug.17PubMed Central. Risk of adverse outcomes during gabapentinoid therapy and factors associated with increased risk in UK primary care using the clinical practice research datalink
Sorting out whether gabapentin is causing, improving, or simply coexisting with a mood change typically requires the kind of careful trial-and-error that happens in a clinical setting: adjusting the dose, monitoring the timeline relative to dose changes, and sometimes cautiously withdrawing the drug to see if symptoms resolve. The reassuring finding across the literature is that gabapentin-related behavioral changes are consistently reversible once the drug is reduced or stopped.