Is it Safe to Mix CBD and Gabapentin?

There is no known interaction between gabapentin and CBD. CBD can change how your body metabolizes certain drugs, but gabapentin hasn’t show conclusive evidence that it is one of them.

What is Gabapentin?

Gabapentin (sold under the brand names Neurontin and Horizant) is an anticonvulsant drug that is used to help people with epilepsy control seizures. It is also approved by the FDA to alleviate neuropathic pain in people suffering from shingles. Shingles are an extremely painful rash that can crop up in people who were infected with the herpes zoster virus, commonly known as chickenpox.

Shingles can develop years or even decades after someone has recovered from herpes zoster and is characterized by shooting nerve pain. Horizant, the brand name extended release version, has also been approved by the FDA to treat restless leg syndrome, a neurological disorder that causes discomfort and an irresistible urge to move the legs.

Gabapentin is also frequently prescribed off label, meaning it’s used to treat conditions other than those approved by the FDA.  Off-label gabapentin prescriptions are used to treat conditions like peripheral neuropathic pain, attention deficit disorder, migraine headaches, fibromyalgia, sleep disorders, anxiety and bipolar disorder.

How Does Gabapentin Work?

Interestingly, how gabapentin works is not really understood. Gabapentin is molecularly similar to the neurotransmitter gamma-aminobutyric acid (GABA) found in the brain. A neurotransmitter is a chemical inside the body that transmits messages within and between nerve cells. GABA is known to be an inhibitory neurotransmitter, meaning that it calms the brain neurons down so they don’t fire so rapidly. Note the similarities between the names GABA and gabapentin.

Gabapentin has been proven to have a similar effect to natural GABA; it inhibits neuron activity and thus stops pain, not at the source, but at the brain level. It can’t stop the nerves in your feet from being painful, but it can block your brain from registering it.

Where the mystery comes in with this medication is that even though gabapentin molecules are similar to GABA, and have similar effects, it does not bind to GABA receptors, boost production of the neurotransmitter or stop it from being destroyed by the body.

How is Gabapentin Metabolized?

Gabapentin is a somewhat strange substance because of how it is metabolized by the human body. Most drugs undergo significant chemical changes as they move through the gut, liver and eventually into the bloodstream. However, gabapentin is different. It really isn’t metabolized at all by the human body. It is excreted almost completely unchanged through the kidneys in urine.

CBD can affect the metabolism of drugs that are processed primarily by the liver because it binds to enzymes, chemicals in the body that speed up chemical reactions. Since gabapentin isn’t metabolized in this way, or at all really, no adverse interaction between the two has yet been noted. Even so, you should still discuss adding CBD with your healthcare team and follow their recommendations.

CBD for Epilepsy

Evidence continues to mount that CBD is a viable treatment for intractable epilepsy, meaning epilepsy that does not respond well to conventional anti-seizure treatments. In 2016, an Israeli study examined the effects of CBD on the number of seizures experienced by children with intractable epilepsy treated in five different clinics. 89% of patients had fewer seizures. More than half of the patients who saw improvement, reported their seizures were reduced by 50% or more. The researchers also noted that the patients were more alert and had an improved quality of life.

Dravet Syndrome

In 2017, researchers in the US conducted a double-blind, placebo controlled study to evaluate the effectiveness of CBD as a treatment for the symptoms of Dravet syndrome, an intractable developmental epilepsy. The researchers concluded that almost half of the patients saw a 50% decrease in seizure activity. Since patients with Dravet syndrome can have hundreds of seizures a month, this is a significant improvement.

Lennox-Gastaut Syndrome

In 2018, another group of US researchers conducted a double-blind, placebo controlled study to investigate CBD as a possible treatment for patients with Lennox-Gastaut syndrome. Lennox-Gastaut is a form of intractable epilepsy that arises in childhood and is a lifelong affliction. The researchers found that 41% of patients given CBD saw improvement in the number of seizures they experienced over a 14 week period.

Epidiolex

These US studies prompted the FDA to approve the first CBD-derived medication available by prescription, Epidiolex. Currently, it is only approved to treat Lennox-Gastaut and Dravet syndromes. Despite this, cannabis is still a Schedule I drug, classified as having no medicinal properties.

CBD for Nerve Pain

Both human and animal studies have shown that CBD has the potential to act as an anti-inflammatory for the nervous system. It’s also thought that CBD has neuroprotective properties, meaning that it may help protect nerve cells from ongoing damage.

A 2018 study found that CBD binds to GABA receptors in the brain. If CBD mimics the effects of GABA, it could help calm the rapid firing of neurons, the same idea behind medications like gabapentin.

CBD has also been shown to slow the breakdown of anandamide, another important neurotransmitter that has a calming effect on the central nervous system. CBD inhibits the actions of the enzyme that destroys anandamide, fatty acid amide hydrolase (FAAH). Higher levels of anandamide have been shown in numerous animal studies to lessen pain response and seizure activity.

Anecdotal Accounts

Anecdotal accounts tout CBD for chronic conditions, like fibromyalgia, that cause chronic nerve pain. Some users state that they have better pain control, were able to reduce their medications and had improved sleep. Others use CBD and gabapentin together and feel that adding CBD gives them better control over their symptoms. Don’t add CBD or change your medications without consulting your healthcare team.

Conclusions

There is no known interaction between CBD and gabapentin. CBD can change the way your body metabolizes certain drugs, but since gabapentin really isn’t metabolized by the body, it may be safe to mix the two. CBD also has the potential to alleviate symptoms of neurological disorders in its own right. Be sure to talk to your healthcare team before adding CBD or changing your medications, and always follow their recommendations.