Gabapentin: Uses, side effects, and what you should know if you've been prescribed this medication

Gabapentin is an anticonvulsant (antiseizure) medication approved by the FDA to treat several conditions. Doctors sometimes prescribe gabapentin "off-label" to treat other conditions as well. A 2022 report stated that gabapentin was among the 10 most commonly prescribed medications in the U.S.

What is gabapentin and what is it used for?

Gabapentin is used to control seizures, to treat nerve pain that can happen after having had shingles, and to treat a condition called restless legs syndrome.

In addition to these FDA-approved uses, doctors sometimes prescribe gabapentin off-label. Off-label use means there is some evidence to show that a drug may be medically appropriate to treat conditions other than those for which it was approved.

Gabapentin is sold under the brand name Neurontin and is available as a generic product as well. (Generic medications are chemically the same as brand-name drugs but may cost less.) Gabapentin is also available as an extended-release tablet that works for a longer length of time; this is the only formulation that is approved for restless legs syndrome.

Gabapentin is taken by mouth and comes in capsule, tablet, and liquid form.

Conditions treated with gabapentin

Gabapentin is FDA-approved as Neurontin to treat partial seizures in adults and children with epilepsy. Partial seizures are convulsions that originate from a single location in the brain.

Neurontin is also approved to treat a type of nerve pain called postherpetic neuralgia, or PHN. PHN can happen after a person has had shingles, an infection from the same virus as chickenpox that causes a painful rash or blisters. Nerve pain from PHN can last for months, or even longer, after the rash has gone away.

An extended-release form of gabapentin is also FDA-approved to treat PHN.

Another extended-release form of gabapentin is FDA-approved to treat restless legs syndrome. This condition causes unpleasant or uncomfortable sensations in the legs and an irresistible urge to move them around, especially at night, which disrupts sleep.

Off-label uses for gabapentin

Doctors often prescribe gabapentin off-label to treat conditions such as:

• pain from diabetic neuropathy, which is numbness or uncomfortable tingling caused by nerve damage from diabetes
• nerve pain in the neck and back from conditions such as sciatica, a painful compression of the sciatic nerve
• hot flashes, which are sudden feelings of heat and sweating that can happen in women after menopause and in those being treated for breast cancer
• mood disorders such as anxiety
• alcohol addiction.

How gabapentin works

In people with partial seizures, gabapentin works by decreasing abnormal activity in the brain. Experts believe gabapentin may cause brain cells to produce more of a chemical called GABA, which reduces abnormal electrical activity of brain cells.

In people experiencing nerve pain after having had shingles, gabapentin is thought to change the way pain signals are sent through the body and brain.

It's not entirely clear how gabapentin works to treat restless legs syndrome.

Side effects of gabapentin

Common side effects of gabapentin include:

• drowsiness or dizziness
• headache or blurred vision
• nausea, vomiting, diarrhea, constipation
• dry mouth
• weight gain
• swelling of the hands, feet, or ankles
• back or joint pain
• flulike symptoms such as fever or body aches.

Rare but serious side effects

Rare but serious side effects of gabapentin include:

• rash, itching, or yellowing of the skin
• swelling of the face and throat, a condition called angioedema
• problems speaking or swallowing
• changes in memory, ability to concentrate, or personality.

Gabapentin may cause breathing problems in people who use opioid pain medicines and those with chronic obstructive pulmonary disease (COPD). Older adults who take gabapentin also are at higher risk of breathing problems.

Because gabapentin can enhance the psychological effect of opioids, it has the potential to be abused and has contributed to drug overdose deaths.

Drugs such as gabapentin have been linked in rare cases to an increased risk of suicidal thoughts or behaviors. If you take gabapentin, you or your family should tell the doctor about any unusual changes in your mood, such as agitation, violence, aggression, depression, or talking about wanting to hurt yourself.

Safely stopping treatment with gabapentin

If you stop taking gabapentin suddenly, there is a chance of having seizures. Instead, you may need to gradually reduce how much gabapentin you take until you stop it completely. Your doctor can advise you on how to safely stop treatment with gabapentin.