Can Gabapentin Cause Atrial Fibrillation (AFib)?

Gabapentin is not widely recognized as a drug that causes atrial fibrillation, but a small and growing body of evidence suggests it can trigger or contribute to AFib in some people. The signal is not strong enough for regulatory agencies to list AFib as a common side effect, and at least one large cohort study found no link at all. Still, a published case report documents new-onset AFib in a young man just days after starting gabapentin, and population-level research in older adults points to a roughly threefold increase in risk compared with other pain medications. The picture is genuinely unsettled, which is exactly why it is worth understanding in detail.

What the Population Data Shows

The most direct look at this question comes from a population-based study that tracked elderly patients who were prescribed gabapentin, pregabalin, opiates, or benzodiazepines and then watched for signs that they had developed AFib. Rather than relying on diagnosis codes alone, researchers used the start of anticoagulant or anti-arrhythmic medication as a practical marker that AFib had been detected and treated. Among those prescribed gabapentin, roughly 9 out of every 1,000 patients went on to start those medications, compared with about 3 out of every 1,000 patients prescribed opiates. That translated to roughly a threefold relative risk. The numbers were similar for pregabalin. The risk did not seem to depend on age or sex within the elderly group, but it did go up with higher doses.¹

A systematic review of the cardiovascular safety of gabapentinoids confirmed this direction. After pooling available data, it found that the initiation of anti-arrhythmia drugs was more than four times higher following the start of a gabapentinoid, and the initiation of anticoagulant or antiplatelet medications was about twice as high. Both findings were statistically robust.²

These are not trivial signals, but they come with caveats. The people in these studies were older, often had chronic pain conditions, and frequently had other cardiovascular risk factors. It is hard to fully separate the drug’s effect from the health profile of the person taking it.

A Study That Found No Link

Not all the evidence points in the same direction. The Multi-Ethnic Study of Atherosclerosis, known as MESA, enrolled nearly 7,000 Americans without known cardiovascular disease and followed them for over a decade. Researchers tracked medication use at multiple check-ins and looked for new cases of clinically detected AFib. In that cohort, gabapentinoid use was not associated with a higher risk of developing AFib compared with not using the drugs at all.³

This is worth pausing on. The MESA cohort was specifically selected to be free of cardiovascular disease at the start, which means participants were healthier than the typical older person prescribed gabapentin. If gabapentin’s AFib risk depends on having pre-existing heart problems, autonomic dysfunction, or kidney disease, a healthier cohort might not show the effect. That does not make the finding irrelevant. It suggests the risk, if real, may be concentrated in people who are already vulnerable rather than spread evenly across everyone who takes the drug.

The Case Report in a Young Patient

One of the more striking pieces of evidence is a published case report of a man in his twenties who developed new-onset atrial fibrillation four days after starting gabapentin for lower back nerve pain. He had no prior cardiac history. The temporal link was tight: the arrhythmia appeared shortly after the drug was introduced, and the clinical team attributed it to gabapentin.⁴

A single case report cannot prove causation on its own. People develop AFib for all sorts of reasons, and coincidence is always possible. But case reports like this one serve an important role in pharmacovigilance: they raise a flag that clinicians should consider the drug when a patient develops an unexplained arrhythmia soon after starting it. The fact that this patient was young and had no other obvious risk factors makes the association harder to dismiss as background noise.

How Gabapentin Might Affect Heart Rhythm

Gabapentin was designed to calm overactive nerve signaling, which is why it works for seizures and nerve pain. But nerves do not only carry pain signals. The autonomic nervous system, the network that controls your heart rate, blood pressure, and other involuntary functions, relies on the same kinds of nerve signaling that gabapentin modifies. Any drug that shifts the balance between the sympathetic (“fight or flight”) and parasympathetic (“rest and digest”) branches of this system can, in theory, affect heart rhythm.

Research on gabapentin’s effects on heart rate variability offers some clues, though the results are not straightforward. In patients with diabetic neuropathy, gabapentin appeared to improve certain measures of cardiac autonomic function over three months. One study found that the drug increased overall heart rate variability and shifted the balance toward parasympathetic activity, which is generally considered a healthier pattern.⁵ A small randomized trial in a similar patient group found a moderate, borderline-significant improvement in heart rate variability as well.⁶

However, an exploratory study in a different population, people with opioid use disorder, found that gabapentin was associated with lower heart rate variability, which is typically a sign of less healthy autonomic function.⁷ The opposing directions in these studies likely reflect differences in the populations being studied, the doses used, and the other drugs on board. But the takeaway is that gabapentin clearly does something to autonomic regulation of the heart. Whether that “something” tips into triggering AFib likely depends on the individual’s baseline cardiac and autonomic state.

The QT Interval Question

When people worry about a drug causing heart rhythm problems, one of the first things to check is whether it prolongs the QT interval, a specific feature of the heart’s electrical cycle that, when stretched, can lead to dangerous arrhythmias. A formal study tested gabapentin enacarbil (a prodrug that converts to gabapentin in the body) at both a standard dose and a dose five times higher in healthy adults. Even at the high dose, there was no meaningful QT prolongation. The maximum change was about 1.3 milliseconds, well below the threshold of concern.⁸

This is reassuring in one specific sense: gabapentin does not seem to cause the kind of arrhythmias that come from QT prolongation, which are typically ventricular (arising in the lower chambers of the heart) and can be life-threatening. Atrial fibrillation, though, is a completely different electrical problem. It originates in the upper chambers and is driven by chaotic electrical signals that have nothing to do with QT length. So a clean QT study does not rule out an AFib risk. The two problems arise from different mechanisms.

Kidney Function as a Hidden Risk Factor

Gabapentin is almost entirely cleared by the kidneys. If your kidneys are not working well, the drug accumulates in your body to levels much higher than intended. This is one of the most plausible pathways by which gabapentin could provoke cardiac problems, including arrhythmias, in certain patients.

A case presented at a nephrology conference described a 69-year-old patient with existing AFib and multiple other conditions who was taking a standard gabapentin dose. After developing acute kidney injury from a contrast dye procedure, the patient became confused, a classic sign of gabapentin toxicity from drug accumulation due to reduced kidney clearance.⁹ While this particular case involved worsening of already-existing AFib rather than new-onset, it illustrates how easily gabapentin levels can climb when kidney function drops. Many older adults have some degree of reduced kidney function without knowing it, and this can silently push gabapentin into toxic territory.

If you are taking gabapentin and have kidney disease, even mild age-related decline in kidney function, your doctor should be checking your kidney labs periodically and adjusting the dose accordingly. This is standard practice in theory, but it does not always happen in reality, especially when gabapentin is prescribed by a pain specialist who may not be tracking kidney function as closely as a primary care doctor would.

Who Is Already at Risk

One important piece of context is just how common existing atrial fibrillation is among people who start gabapentin. A recent analysis of nearly 250,000 Medicare beneficiaries who were newly prescribed gabapentin found that about 16 percent already had an atrial fibrillation diagnosis before they started the drug. Among those who continued gabapentin for more than six months, that figure was slightly higher, around 17 percent.¹⁰

This matters for two reasons. First, it means a large share of gabapentin users are already living with the exact arrhythmia in question, so any worsening of their AFib might be attributed to disease progression rather than to the drug. Second, it raises the possibility that some of the AFib signal in population studies reflects the fact that gabapentin is being prescribed to a sicker, more cardiovascularly burdened group of patients. Researchers try to control for this kind of confounding, but it is notoriously difficult to completely eliminate.

Gabapentin’s Broader Cardiovascular Profile

AFib is not the only cardiovascular concern that has surfaced with gabapentin. A large study of patients with diabetic neuropathy found elevated risks for several cardiovascular events among gabapentin users compared with matched controls. The highest risk was seen for deep vein thrombosis, followed by pulmonary embolism, peripheral vascular disease, stroke, heart attack, and heart failure. Some of these associations appeared even with short-term use of three months or less.¹¹

These findings do not prove that gabapentin directly damages blood vessels or the heart. Diabetic neuropathy patients already carry high cardiovascular risk, and untangling drug effects from disease effects is inherently difficult in this population. But the pattern across multiple cardiovascular outcomes suggests the relationship between gabapentin and the cardiovascular system deserves more scrutiny than it has traditionally received. For years, gabapentin was considered almost uniquely safe among pain and seizure medications because it has few drug interactions and is not metabolized by the liver. The emerging cardiovascular data suggests that framing was incomplete.

What Happens When You Stop Gabapentin

Abruptly stopping gabapentin can trigger a withdrawal syndrome that sometimes includes cardiovascular symptoms. In one documented case, a patient developed severe chest pain and high blood pressure about ten days after gabapentin was tapered and discontinued. The cardiac workup, including an electrocardiogram and imaging, came back normal, and the symptoms resolved within a day or two of restarting gabapentin.¹²

This is worth knowing because if someone develops palpitations or chest symptoms around the time of a gabapentin dose change, the direction of the change matters. New symptoms after starting the drug raise different concerns than symptoms that appear after stopping or reducing it. Withdrawal-related cardiovascular symptoms are thought to result from the nervous system rebounding after it had adapted to the drug’s calming effect, essentially, the opposite of what the drug was doing. If you need to stop gabapentin, a slow taper under medical supervision is the standard recommendation.

Practical Considerations for People Taking Gabapentin

If you are currently taking gabapentin and have no history of heart rhythm problems, the evidence does not suggest you need to panic. The absolute risk of developing AFib from gabapentin appears to be low, even in the studies that found an elevated relative risk. In the population study that showed roughly a threefold increase, the actual rate was still only about 9 per 1,000 patients. Most people taking gabapentin will not develop AFib from it.

That said, certain factors should raise the level of attention:

Reduced kidney function: Gabapentin can accumulate when the kidneys are not clearing it efficiently, raising the risk of toxicity and potentially cardiac effects.
Existing heart conditions: If you already have AFib, heart failure, or other structural heart disease, the drug’s autonomic effects may matter more.
High doses: The population data showed a dose-dependent relationship, meaning higher doses carried more risk.
New symptoms after starting: Palpitations, a racing heart, dizziness, or the sensation that your heart is fluttering within the first days to weeks of starting gabapentin warrant a conversation with your doctor, not necessarily stopping the drug on your own, but having the rhythm checked.

Gabapentin remains a useful medication for nerve pain, seizures, and several other conditions. The point is not to avoid it but to be aware that “safe for the heart” is not as airtight a label as it once seemed. If you have risk factors for AFib, particularly older age, existing heart disease, or impaired kidneys, it is reasonable to ask your prescriber whether the dose accounts for those factors and whether periodic monitoring makes sense. For younger, otherwise healthy individuals, the risk appears to be very low, though the case report of AFib in a man in his twenties is a reminder that rare events can still happen to anyone.