Gabapentin is used primarily to treat seizures and neuropathic pain. It is also commonly prescribed for many off-label uses, such as treatment of anxiety disrders, insomnia, and bipolar disorder.
There are, however, concerns regarding the quality of the trials conducted and evidence for som such uses, especially in the case of its use as a mood stabilizer in bipolar disorder.
Gabapentin is approved for treatment of focal seizures and mixed seizures. There is insufficient evidence for its use in generalized epilepsy.
A 2010 European Federation of Neurological Societies task force clinical guideline based on available evidence recommended gabapentin as a first-line treatment for diabetic neuropathy and postherpetic neuralgia with its highest level of evidence it also recommended gabapentin as a first-line treatment for central pain but with lower evidence. It also found good evidence that a combination of gabapentin and morphine or oxycodone or nortriptyline worked better than either drug alone; the combination of gabapentin and venlafaxine may be better than gabapentin alone.
A 2017 Cochrane review found evidence of moderate quality showing a reduction in pain by 50% in about 15% of people with postherpetic neuralgia and diabetic neuropathy. Evidence finds little benefit and significant risk in those with chronic low back pain. It is not known if gabapentin can be used to treat other pain conditions, and no difference among various formulations or doses of gabapentin was found.
A 2010 review found that it may be helpful in neuropathic pain due to cancer. It is not effective in HIV-associated sensory neuropathy and does not appear to provide benefit for complex regional pain syndrome.
A 2009 review found gabapentin may reduce opioid use following surgery, but does not help with post-surgery chronic pain. A 2016 review found it does not help with pain following a knee replacement.
It appears to be as effective as pregabalin and costs less.
All doses appear to result in similar pain relief.
The American Headache Society (AHS) and American Academy of Neurology (AAN) guidelines classify gabapentin as a drug with “insufficient data to support or refute use for migraine prophylaxis. Furthermore, a 2013 Cochrane review concluded that gabapentin was not useful for the prevention of episodic migraine in adults.
Gabapentin has been used off-label for the treatment of anxiety disorders. However, there is dispute over whether evidence is sufficient to support it being routinely prescribed for this purpose.
Gabapentin may be useful in the treatment of comorbid anxiety in bipolar patients, (however not the bipolar state itself). Gabapentin may be effective in acquired pendular nystagmus and infantile nystagmus, (but not periodic alternating nystagmus). It is effective in hot flashes. It may be effective in reducing pain and spasticity in multiple sclerosis. Gabapentin may reduce symptoms of alcohol withdrawal (but it does not prevent the associated seizures).
There is some evidence for its role in the treatment of alcohol use disorder; the 2015 VA/DoD guideline on substance use disorders lists gabapentin as a “weak for” and is recommended as a second-line agent. Use for smoking cessation has had mixed results. Gabapentin is effective in alleviating itching in kidney failure (uremic pruritus) and itching of other causes. It is an established treatment of restless legs syndrome. Gabapentin may help sleeping problems in people with restless legs syndrome and partial seizures. Gabapentin may be an option in essential or orthostatic tremor.
Gabapentin is not effective alone as a mood-stabilizing treatment for bipolar disorder. There is insufficient evidence to support its use in obsessive compulsive disorder and treatment-resistant depression. Gabapentin does not appear effective for the treatment of tinnitus.