Key Points

  • Gabapentin is a medication used to treat conditions including shingles, diabetic neuropathy and partial seizures.
  • Exceeding a maximum dose of 600 mg three times per day can lead to an overdose.
  • While it is possible to overdose on gabapentin alone, many overdose deaths involve polysubstance use.
  • The main cause of Gabapentin overdose is misuse.

Gabapentin is a potent medication that should only be used as prescribed. Anyone taking this medication should understand that using higher-than-prescribed doses, doubling doses, or using Gabapentin recreationally can lead to an overdose. A Gabapentin overdose can be life-threatening, causing both physical and mental harm. It is a medical emergency that requires immediate treatment to maximize the chances of recovery. In this blog, we will discuss what leads to Gabapentin overdose, the symptoms to watch for, and the treatments necessary for recovery.

What is Gabapentin?

Gabapentin, the generic name for the brand name medications Neurontin, Horizant, and Gralise, is an FDA-approved drug used to treat partial seizures, restless leg syndrome, and neuropathic pain caused by conditions such as shingles, postherpetic neuralgia and diabetic neuropathy. It belongs to a class of medications known as anticonvulsants. As an anticonvulsant, gabapentin works by binding to a specific site in the nervous system called the alpha-2-delta, helping to relieve nerve pain and reduce seizure risk, according to Drugs.com. For epilepsy and nerve pain, treatment typically begins with an initial dose of 300 mg once daily on the first day.[2] On the second day, the dose increases to 300 mg twice daily, followed by 300 mg three times daily on the third day. A maintenance dose of 300 mg to 600 mg three times daily may then be prescribed, depending on individual needs. While effective for many patients, gabapentin may cause side effects in individuals between the ages of 18 and 60, including aggression, thought disturbances, excessive drowsiness, and sexual dysfunction. Because taking more than prescribed can lead to overdose, gabapentin should be used only as directed by a healthcare provider.

What is an Overdose?

The National Harm Reduction Coalition defines an overdose as a situation in which a toxic amount of a drug — or combination of drugs — overwhelms the body and causes adverse effects.[3] Overdoses can occur with many substances, including over-the-counter medications, but prescription drugs are often involved because they are easier to obtain. While some people intentionally take large amounts of medication, overdoses are not always deliberate. Toxicity often develops when someone has built a tolerance to the effects of the drug after prolonged use or taking high doses. Although the person may not feel the effects as strongly, the body can still reach toxic levels, leading to an overdose. In other cases, overdoses happen accidentally, such as when a pill is laced with another dangerous substance like fentanyl.

What Causes Gabapentin Toxicity?

The primary cause of gabapentin overdose is drug misuse. According to the National Library of Medicine, drug misuse is defined as using a substance in a way that is not consistent with legal or medical guidelines.[5] This can include taking the medication in a manner other than prescribed, doubling doses, or combining it with other drugs to induce a high. Misusing gabapentin can lead to serious health and social consequences. These may include mental health issues such as suicidal thoughts, depression, and paranoia, as well as physical health problems such as cardiac complications and overdose.[5] Unfortunately, individuals who misuse gabapentin face a significantly higher risk of overdosing. Reasons for gabapentin misuse can vary. Some individuals may misuse their prescription due to peer pressure, to avoid physical or emotional pain, to escape difficult situations, or to fit in with a certain group.

What Are the Warning Signs of a Gabapentin Overdose?

While it is possible to overdose on gabapentin, death from a gabapentin-only overdose is rare. In most fatal cases where gabapentin is detected, other substances—particularly opioids—are also involved. According to the Centers for Disease Control and Prevention (CDC), gabapentin is sometimes used to potentiate the effects of illicit opioids.[6] Data shows that reports of gabapentin exposure associated with intentional abuse, misuse, or unknown exposure to U.S. poison control centers increased by 104% between 2013 and 2017.[6] The percentage of overdose deaths involving gabapentin that also involved opioids rose from 49.4% in the first quarter of 2019 to 90% in the last quarter of 2020. Nearly all of these opioid-related cases involved fentanyl.[6] Because of this, the symptoms of a gabapentin overdose can be overshadowed by those of an opioid overdose, which may include:[7]
  • Pinpoint pupils
  • Falling asleep or losing consciousness
  • Respiratory depression
  • Limp body
  • Choking or gurgling sounds
  • Cold, clammy skin
  • Bluish lips or nails
Signs of a gabapentin (Neurontin) overdose without opioid involvement can include:[8]
  • Low blood pressure
  • Rapid heartbeat
  • Dizziness
  • Nausea or vomiting
  • Impaired coordination
  • Lethargy
  • Coma
  • Death
If you or someone you know has taken too much gabapentin, call the Poison Center immediately at 1-800-222-1222. If symptoms such as difficulty breathing or an irregular heartbeat occur, call 911 for medical attention right away.

What is the Treatment for a Gabapentin Overdose?

The approach to treating a gabapentin overdose depends on whether the drug is present alone or in combination with an opioid.
  • Gabapentin-only overdose:[9] Treatment typically involves dialysis in a hospital setting to help remove the drug from the bloodstream. If the patient has reduced kidney function or is in a coma, mechanical ventilation may be required to support breathing.
  • Gabapentin and opioid overdose:[10] If an opioid is involved, the first step is administering naloxone (Narcan) to reverse the opioid’s effects on the central nervous system. The patient should then receive inpatient care, which can include respiratory support and interventions to stabilize their heart rate and blood pressure.
Additional treatment measures may include:
  • Activated charcoal – to help decontaminate the gastrointestinal tract.
  • Bowel irrigation – to remove drug packets from the system.
  • Buprenorphine – if the patient is in respiratory arrest and meets the criteria for its use.

How to Prevent a Gabapentin Overdose?

The most effective way to prevent a gabapentin overdose is to take the medication exactly as prescribed and only for the duration recommended by your healthcare provider. Because gabapentin can enhance the effects of opioids, it should not be taken alongside prescription opioids unless specifically directed and closely monitored by a physician. If you develop a new or worsening condition that requires stronger medication in addition to gabapentin, speak with your doctor or pharmacist. They can help you determine the safest treatment plan and reduce the risk of accidental overdose.

Getting Help for Gabapentin Addiction

Individuals who have overdosed on a combination of gabapentin and opioids may require further treatment to prevent recurrence. This can include inpatient care in a drug or alcohol rehabilitation facility, where they can be medically monitored, safely detox from opioids, and receive FDA-approved medications to manage withdrawal symptoms and cravings. Outpatient addiction treatment services may also be recommended, such as therapy for opioid use disorder (OUD) or substance use disorder (SUD), to provide ongoing recovery support.