How Long Does Gabapentin Stay in Your System?

Gabapentin is most recognizable by the brand name Neurontin, but there are numerous generic forms of gabapentin on the market and other brands of gabapentin (Gralise, Horizant, and others). Gabapentin is also used for numerous other purposes, including:

• Other forms of pain that are not related to nerve issues
• Anxiety that occurs in certain types of psychological disorders, such as bipolar disorder
• Restless leg syndrome
• Withdrawal symptoms from alcohol and other drugs

The above uses are referred to as off-label uses, meaning that they are not formally approved by the Food and Drug Administration (FDA) for that purpose, but there is research and clinical evidence to suggest that the drug can be useful in addressing these issues. Gabapentin is often used in conjunction with other drugs to treat specific conditions, including seizures, pain, and anxiety, as opposed to being used by itself.

Because gabapentin is considered to have a relatively benign side effect profile and does not have significant interactions with many other medications, it is commonly used in the treatment of numerous other issues. The doses of the drug used for medical purposes will depend on the type of condition being addressed. The effectiveness of gabapentin may be diminished for treating pain at higher doses.

How Gabapentin Works

Gabapentin is not a controlled substance listed by the Drug Enforcement Administration (DEA), but it does require a prescription from a physician in order to legally obtain it. It is most often listed as an anticonvulsant drug, and it is believed to mimic the actions of the neurotransmitter gamma-aminobutyric acid (GABA). Therefore, many sources refer to gabapentin as a GABA analogue, meaning that its structure is believed to be similar to the structure of this neurotransmitter.

Neurotransmitters are chemical substances in the brain that are released by the nerve cells in the brain (referred to as neurons) that allow the brain cells to communicate with one another and give a person the ability to perform nearly all the actions they perform. GABA is the major inhibitory neurotransmitter in the brain, meaning when this substance is released, it results in decreasing the activity of other neurons in the brain.

Although gabapentin does not directly affect the receptors in the brain that are specialized for GABA, it does appear to reduce the activity of other neurons but through a different but unknown mechanism. This accounts for gabapentin’s ability to address issues like seizures (which are typically the result of overly active areas of the brain), pain, and anxiety.

Although it is used to address issues with pain, gabapentin is not considered to have the addiction potential that other prescription pain medications like opiate drugs have, and it is not as effective as relieving pain as many of the opiate drugs are. Physicians will often prescribe gabapentin with other drugs, and this combination of drugs can result in a more effective treatment of the specific issue at hand.

Gabapentin Half-Life

Gabapentin is available in immediate-release and extended-release versions. It is most often taken as a pill. Information on the drug suggests that the half-life of gabapentin in most people is between 5-7 hours. The half-life of a drug refers to the time that it takes a person’s system to break the drug down to half of its original or beginning concentration in the bloodstream.

The liver is the organ that is responsible for breaking down (metabolizing) most of the substances in a person’s system. However, gabapentin is one of the few drugs that is not metabolized by the liver; instead, it is primarily metabolized by the kidneys. Because of this unique process, gabapentin does not remain in the body very long.

Gabapentin would be totally eliminated from the systems of most people after a span of five to eight half-lives has transpired. If we consider that the average half-life of gabapentin is around seven hours in most people, it would take about 48 hours for the drug to be totally eliminated from the system; however, there other factors that can affect this process. For instance, extended-release versions of gabapentin would continue to release the drug over time, and the detectability of the drug would be extended.

How Long Does Gabapentin Remain in the Body?

Drug screens typically do not test for the presence of gabapentin, but the substance can be detected if instructions are made to specifically look for the drug.

• The detectability of gabapentin will range from five to seven hours for most blood tests.
• It is undetectable in saliva swab tests.
• Hair tests might be able to specifically detect the presence of gabapentin for up to 90 days; however, it would be highly unusual for a hair test to be used to detect gabapentin.
• Urinalysis can detect the presence of gabapentin for up to three days in most individuals. The range of detection for urine tests would span from one to three days in most cases. Urinalysis would be the most common method to test for gabapentin.

Because of the way gabapentin is metabolized, the dosage may have less of an effect on the length of time the drug remains in the system compared to how dosages can alter the elimination time for many other drugs. Even so, taking very high doses of gabapentin could lead to longer elimination times for the drug.
Other factors affect the elimination of gabapentin from the body. The age of the person can affect this process, with older individuals experiencing longer elimination times than younger individuals. Differences in kidney functioning would obviously affect the elimination time of the drug. In addition, the person’s body mass index or weight would affect the elimination time for gabapentin, with heavier people eliminating it more quickly.

Finally, hydration could conceivably speed up the elimination of gabapentin from an individual’s system since the drug is primarily metabolized in the kidneys and eliminated through the urine. More frequent urination could conceivably speed up the process of elimination of the drug.