Gabapentin For Anxiety: What You Need To Know

Generalized anxiety disorder (GAD) is a common condition that affects 3.1% of the U.S. population,¹ and women are more likely² than men to be affected. One study³ found that lifetime prevalence rates for any type of anxiety disorder are 30.5% for women and 19.2% for men. 

A report by the World Health Organization (WHO)⁴ in 2017 found that anxiety disorders are the sixth most common disorders causing significant disability in people’s lives in highly developed countries. 

If you struggle with anxiety, you may be prescribed gabapentin to help to control your symptoms. Here’s what you need to know about anxiety, how gabapentin might help, how long it might take to start working, and what side effects or special precautions you need to be aware of while under medication. 

What is anxiety disorder?

Occasional anxiety is normal; everyone experiences it at certain times in their life. It only becomes concerning when your anxiety symptoms start to interfere with your daily functioning. 

Some symptoms of anxiety disorder that you may experience include the following:

• Frequently feeling nervous, irritable, or on edge

• Feeling a sense of impending doom or danger

• A range of physical symptoms including having an increased heart rate (heart palpitations), sweating abnormally, shaking or trembling, and breathing rapidly (hyperventilating)

• Having difficulty concentrating or focusing

• Having difficulty sleeping because you are feeling anxious

• Experiencing nausea, abdominal pain, or diarrhea

If you struggle with an anxiety disorder, you may find that you have excessive and persistent worry or fear about everyday situations. 

You may have repeated episodes of intense fear and anxiety (commonly called panic attacks) that may be so severe it can feel as though you are having a heart attack. You may also find that you start adapting your lifestyle to avoid situations or activities that trigger your anxiety.

Symptoms of an anxiety disorder often start in childhood or adolescence⁵ and continue into adulthood. 

Different types of anxiety disorders

Aside from GAD, there are other types of anxiety disorders, including social anxiety disorder, phobias, and panic disorder (panic attacks). 

You may also experience anxiety as part of mixed anxiety and depressive disorder, in which case you may experience symptoms of both conditions.

Generalized anxiety disorder

• Persistent, excessive worry about routine events or situations

• Disproportionate worry that is difficult to control

• Your anxiety impacts your ability to function

Agoraphobia

• Fear of being in places or situations that may cause you to feel trapped, helpless, or embarrassed 

• Avoidance of situations or places that cause you to feel trapped, helpless, or embarrassed

• In severe cases, you may feel too afraid even to leave home

Panic disorder

• Repeated episodes of intense fear, worry, or terror that reach a peak within a few minutes

• Associated with physical symptoms such as shaking, shortness of breath, sweating, nausea, and heart palpitations

• Physical symptoms can be so severe that you believe you are having a heart attack or are about to die

• You may develop a fear of having further panic attacks

Anxiety disorder caused by a medical condition

Anxiety can be triggered by an underlying medical condition such as an overactive thyroid. Usually you would have symptoms of anxiety as well as of the underlying medical condition.

Social anxiety disorder

• High levels of anxiety or fear around social situations

• Feeling abnormally self-conscious in the company of others

• May lead to avoidance of social situations

• Disproportionate fear or concern about being judged negatively by others

Specific phobias

• Major anxiety about being exposed to a certain trigger or situation

• Avoidance of your specific trigger

• You may experience panic attacks in response to your trigger

Substance-induced anxiety disorders

• Intense feelings of anxiety or panic related to taking or misusing certain drugs or medications 

Childhood anxiety disorders such as separation anxiety disorder and selective mutism

• Present in childhood

• May sometimes continue into adulthood

• Interfere with school and/or social functioning

Causes of anxiety disorders

The exact cause of anxiety is not fully known. It is likely that anxiety disorders are caused by a combination of factors, including both your genes and your environment.

Genetics are known to play a role in the development of anxiety disorders. You are more likely to develop it if you have a blood relative who suffers from it.

There is evidence to suggest that an imbalance in your neurotransmitters⁶ may also play a role in the development of anxiety disorders. People with low serotonin activity and elevated noradrenergic system activity may be more prone to developing it.  

The following factors have been identified as putting you more at risk of developing an anxiety disorder:

• Trauma

• Stress as a result of ill health

• Excessive or persistent life stressors

• Some personality types may be more prone to developing anxiety disorders

• Drug or alcohol use or misuse

• Other mental health disorders such as depression or substance abuse

Treatment of anxiety

The main treatment for anxiety disorders is medication together with psychotherapy, such as cognitive behavior therapy. Lifestyle modifications such as exercising and mindfulness practice can also be effective as part of your treatment regimen. 

Traditionally, medications used to treat anxiety include selective serotonin reuptake inhibitors (SSRIs), serotonin noradrenaline reuptake inhibitors (SNRIs), and benzodiazepines. Buspirone has also been used in the short-term management of anxiety. 

Although these medications are generally effective, they may not provide relief for everyone; in some people, they may even have unwanted side effects. 

If your anxiety doesn’t respond to any of the standard medications for anxiety or if you suffer intolerable side effects from them, your doctor may consider using gabapentin off-label to treat your anxiety. 

Gabapentin for anxiety

Gabapentin was originally registered⁷ for the treatment of nerve pain and seizures, but has since been used off-label for the treatment of various other disorders including anxiety. 

Pregabalin is a molecule with a similar structure to gabapentin (think of pregabalin as a cousin to gabapentin) that has been approved for the treatment of anxiety in Europe. However, it is only used off-label for anxiety disorders in the U.S. 

What do the studies show?

Gabapentin has been shown to decrease symptoms of anxiety⁸ in animals. Although there are numerous clinical trials⁷ showing the efficacy of pregabalin in the treatment of anxiety disorders, there are fewer good-quality trials supporting the use of gabapentin in the management of anxiety.  

One study of 420 breast cancer survivors with non-specific symptoms of anxiety found that gabapentin taken for eight weeks helped reduce anxiety symptoms.⁹ 

Breast cancer survivors were asked to rate their anxiety at the start of the study. After four weeks of taking gabapentin 300mg, gabapentin 900mg, or a placebo, they were asked to do the rating again. 

Anxiety levels were significantly decreased in the patients taking gabapentin versus the placebo. The more severe the anxiety to start with, the more significant the response to gabapentin appeared to be. 

There was an initial increased dose response to the higher dose of gabapentin, but this disappeared by eight weeks of treatment. The reduction in anxiety was maintained after eight weeks in the treatment group. 

A small, but good-quality study evaluated the effect of gabapentin versus placebo¹⁰ in people with social phobia. After 14 weeks of treatment, social phobia symptoms had improved significantly in the group taking gabapentin versus the group taking the placebo. 

Another study looked at the use of gabapentin in panic disorder¹⁰ and found that gabapentin was superior to placebo in severely ill patients. However, there was no significant difference between symptom resolution in the treatment and placebo groups in less severely ill patients. 

Some small studies have found that gabapentin is effective in reducing anxiety¹⁰ prior to surgery as a single preoperative dose. However, other studies have not been able to replicate the findings, so further research needs to be done to provide definitive evidence. 

There is a lack of good-quality trials assessing the use of gabapentin for GAD. However, there is one very in-depth case study evaluating the use of gabapentin for treatment-resistant GAD.⁸ The patient being studied had previously tried SSRIs, SNRIs, and various other drugs for anxiety, all to no avail. 

The study results suggest that there is potential for use of gabapentin in GAD. The patient had a positive response to treatment with gabapentin. Anxiety symptoms were rated as low or non-existent when she was on daily doses of gabapentin equal to or more than 900mg a day. 

As this is a single-patient case study, the results cannot be extrapolated to other people suffering from GAD. However, it does suggest that there is scope for further, good-quality studies evaluating the use of gabapentin in GAD. 

Taking gabapentin for anxiety

Gabapentin is usually taken three times a day. The dosage varies for different people. It may take awhile for your doctor to get the right dose for you. 

Usually, you will be started on a low dose, which will be titrated up depending on your response. This also gives your body time to get used to the medicine. 

Although gabapentin was shown to reduce anxiety after a single dose¹⁰ in the studies evaluating its use preoperatively, it may take a few days for your body to reach therapeutic levels. 

You should not stop taking gabapentin without discussing it first with your doctor, as stopping gabapentin abruptly can cause withdrawal effects. Your doctor will tell you how to titrate your dose down when you want to stop it. 

Side effects of gabapentin

Gabapentin is generally considered safe and usually well-tolerated. However, there are some side effects you should be aware of if you are using it to treat your anxiety. 

The most common side effects¹¹ of gabapentin are:

• Dizziness

• Weight gain

• Dry mouth

• Unsteadiness when walking

• Double or blurred vision or eyes moving from side to side

• Drowsiness

• Shaking

There has been some concern that gabapentin may have potential for abuse.⁸ However, this appears to be an issue only in people with substance abuse disorders or when doses of gabapentin are over 3,000mg per day. 

The lowdown

When traditional medications are not effective for anxiety or if the side effects are intolerable, your doctor may consider using gabapentin off-label for your anxiety.

Gabapentin is not registered for use in the management of anxiety in the U.S. However, doctors use it off-label to treat anxiety disorders. 

While there are some studies showing its efficacy for certain types of anxiety, more studies need to be done to properly evaluate the effectiveness of gabapentin in treating generalized anxiety disorder.