Can gabapentin lower your blood pressure?

In this article:

• Can gabapentin lower blood pressure?
• Gabapentin and blood pressure
• Who might experience blood pressure changes?
• What to look out for
• When to see a doctor
• The bottom line

In this article

• Can gabapentin lower blood pressure?
• Gabapentin and blood pressure
• Who might experience blood pressure changes?
• What to look out for
• When to see a doctor
• The bottom line

Approximately 73 million people in the U.S. take prescription gabapentin to treat nerve pain, manage conditions like postherpetic neuralgia and restless legs syndrome (RLS), or as a therapy for partial-onset seizures. 

There are several known gabapentin side effects, including dizziness, fatigue, and swelling of the hands and feet. While some people may experience a drop in blood pressure after acute use of the drug, lowered blood pressure is not a common side effect of long-term use.

Does gabapentin cause lower blood pressure?

“Gabapentin does not directly influence blood pressure. However, some patients experience a drop in blood pressure, especially older adults,” explains Erika Gray, Pharm.D., founder and chief medical officer at ToolBox Genomics.com. “The Federal Drug Administration labels drops in blood pressure (hypotension) as an infrequent side effect for gabapentin. ” 

Clinical trials of gabapentin, brand name Neurontin, have not shown a statistically meaningful change in blood pressure; however, studies conducted on humans for this exact topic are few and far between. 

In a very niche study on patients who underwent microvascular breast reconstruction, those who received gabapentin had more postoperative hypotensive events, also known as sudden drops in blood pressure after surgery.

Additionally, gabapentin may have some other cardiovascular side effects, including hypotension and peripheral edema (swelling in your legs, ankles, or feet). However, long-term use of the drug does not typically result in sustained lowered blood pressure. 

How might gabapentin influence blood pressure?

“Gabapentin’s effect on blood pressure is not directly from the medication,” explains Dr. Gray. “Instead, the change in blood pressure may be caused by sedation of the central nervous system, which decreases the sympathetic (fight or flight) signaling in the brain.”

Gabapentin is an anticonvulsant drug that works by blocking nerve signals. It binds to subunits of voltage-dependent calcium channels in the nucleus tractus solitarii in the brainstem. This attachment prevents calcium entry, which changes how nerve cells signal and influence things like heart rate or blood pressure. As a result, gabapentin regulates the neurotransmitters, or chemical messengers, responsible for making you feel pain or go into seizures. 

When these brain chemicals change, your muscles tighten less, and your blood vessels relax. That means your body isn’t squeezing as hard (it has lowered arterial pressure), which allows blood to flow more easily. This can result in lower blood pressure. Hence, gabapentin doesn’t have a direct mechanism of action on cardiovascular responses, but it can indirectly influence them.

In a study on rats, researchers found that acute administration of gabapentin lowered both blood pressure and heart rate within 30 minutes of receiving the injection. The effect was more pronounced in hypertensive rats (those with high blood pressure) versus their normotensive (those with normal blood pressure) counterparts. 

This happens because gabapentin reduces the levels of norepinephrine in plasma. Norepinephrine is a chemical compound responsible for your fight-or-flight reaction. It constricts your blood vessels, raising your blood pressure. So when gabapentin comes along and changes how much norepinephrine is released, it has a hemodynamic effect, changing how the heart and blood vessels respond, and decreases sympathetic nerve transmission, your body’s stress-related nerve signals. This could result in a decrease in blood pressure.

Proven benefits of gabapentin

A healthcare provider may prescribe you gabapentin for several reasons. 

Manages pain

One of the most common reasons someone may be prescribed gabapentin is to control chronic pain. While not a traditional analgesic, gabapentin does have pain-reducing effects. In a large review of 29 studies on the effects of the drug, researchers found 43% of people saw improvement in neuropathic pain levels when using gabapentin, compared to 26% who saw improvement with a placebo.

The drug reduces pain by blocking nerve signals that transmit pain sensation. This sedation may also have a hypotensive effect, reducing high blood pressure.

Controls seizures and treats epilepsy

Gabapentin has long been a treatment option for people who have epilepsy or experience seizures. In a double-blind study of 127 patients with drug-resistant partial epilepsy, 25% of people who received 1,200 milligrams of gabapentin a day saw the number of partial seizures they experienced reduced by 50% or more.

This happens because gabapentin keeps brain cells from overacting in the way they would during a seizure, reducing the overall electrical activity in the brain. When you take gabapentin for seizures or epilepsy, you could experience a drop in blood pressure because the drug also affects the central nervous system.

Treats restless legs syndrome

Gabapentin comes in many forms, including capsules, tablets, and liquids, as well as immediate- and extended-release options. There is a type of gabapentin known as gabapentin enacarbil, a prodrug that converts to gabapentin only after it’s absorbed in the body.

Oral gabapentin enacarbil has proven to be highly effective at treating restless legs syndrome in doses of 600 milligrams a day or more. The drug slows nerve signaling to prevent periodic limb movements, but it may also slow your central nervous system enough that you have a drop in blood pressure.

Treats hot flashes

One little-known use of gabapentin is the treatment of hot flashes. In a study of 66 breast cancer survivors, those who used gabapentin saw about a 66% reduction in hot flashes. It should be noted that only about one-third of those patients preferred using gabapentin, while the majority preferred venlafaxine.

Both drugs affect temperature regulation. Gabapentin affects your central nervous system by reducing hyperactivity. While this attenuates (or helps reduce) hot flashes, it may also cause a drop in blood pressure.

Reduces stress and anxiety

The FDA has not approved gabapentin as a standalone treatment for stress and anxiety. However, there is some evidence that there is an inverse relationship between the drug and anxiety levels. This is due to the drug’s ability to calm nerve activity, which may also lead to a drop in blood pressure.

Who might experience blood pressure changes on gabapentin?

A few groups of people may be especially susceptible to experiencing lowered blood pressure while on gabapentin, according to Dr. Erika Gray:

• Older adults: Older adults are more sensitive to sedation, which can increase the risk of falls, dizziness, and lowered blood pressure.
• People on high dosages: Dosages of 1,800 milligrams a day could increase the drug’s sedative effects, and low blood pressure is a symptom of a gabapentin overdose.
• Patients already taking sedatives: If you’re on opioids, antihypertensives, or benzodiazepines, you may experience increased levels of sedation and adverse side effects.
• Those with chronic kidney disease: The kidneys excrete gabapentin, so limited function could lead to toxic levels of the drug in the system and severe drops in blood pressure, among other side effects.
• Those with heart disease: Due to the cardiovascular effects gabapentin has, it is often contraindicated for people with heart disease.

Alert your healthcare provider to any medications or other supplements you take to avoid potential drug-drug interactions.

Recognizing the signs

Low blood pressure, also called hypotension, presents with the following symptoms:

• Dizziness or lightheadedness
• Fatigue or drowsiness
• Trouble concentrating
• Nausea
• Blurred vision

“The most common symptoms are dizziness, lightheadedness, and a feeling of weakness and fatigue, says Tariqshah Syed, MD, chief of cardiology at Holy Name Medical Center in Teaneck, New Jersey. “If blood pressure is too low, patients may pass out.”

Gabapentin can have severe adverse side effects, including heart failure, so follow your healthcare provider’s medical advice when it comes to gabapentin dosage as well as monitoring side effects.

When to contact your healthcare provider

If you are using gabapentin and notice significant changes in your blood pressure, you should contact your healthcare provider right away. 

“If your systolic blood pressure goes below 90 mmHg, seek medical attention,” warns Dr. Tariqshah Syed, MD. “Also, if there is a change in your mental status, that should be addressed and treated emergently.”

Dizziness and lightheadedness are common gabapentin side effects. However, if these symptoms become severe or you experience difficulty breathing or swelling in your extremities, you should immediately contact a healthcare professional.

The bottom line

While lowered blood pressure isn’t a common side effect of gabapentin, the drug could result in acute instances of hypotension. It works to calm your central nervous system and sympathetic nervous system, which is beneficial for those who are living with chronic pain or seizures. However, a byproduct of this could be a drop in blood pressure.