Gabapentin for Bipolar Disorder

Overseen By James J Prisciandaro, PhD

Age: 18+

Sex: Any

Trial Phase: Phase 2

Sponsor: Medical University of South Carolina

Must be taking: Mood stabilizers

Must not be taking: Benzodiazepines, Opioids, Barbiturates, others

Disqualifiers: Schizophrenia, Epilepsy, Brain injury, others

Prior Safety Data This treatment has passed at least one previous human trial

Compensation: Varies

Number of Visits: 5

Duration: 2.5 weeks

68 Participants Needed

Trial Summary

What is the purpose of this trial?

This research study evaluates the effects of an FDA-approved medication Gabapentin in individuals with Bipolar Disorder who smoke marijuana. Participants in the study will will be assigned to take either Gabapentin or a matched placebo. Study medication will be taken for 17 days. There will be 5 study visits, with 2 MRI brain imaging scans completed. Questionnaires and clinical interview measures will be completed at study visits along with consistent assessment of potential side effects from study medication.

Will I have to stop taking my current medications?

The trial requires participants to be on a daily mood stabilizing medication, but you cannot take certain medications that interfere with gabapentin, like benzodiazepines or opioids. If you're on any of these, you might need to stop them to join the trial.

What data supports the effectiveness of the drug Gabapentin for treating bipolar disorder?

Research suggests that Gabapentin may help in maintaining stability and treating some symptoms in bipolar patients, as studies have evaluated its use in reducing relapse rates and as an add-on therapy. ^{1 2 3 4 5}

Is gabapentin generally safe for humans?

Gabapentin has a good safety profile, meaning it is generally safe for humans, and it doesn't require special monitoring or have many drug interactions. ^{3 5 6 7 8}

How is the drug gabapentin unique for treating bipolar disorder?

Gabapentin is unique for treating bipolar disorder because it is primarily an anti-epileptic drug, but it is being explored as an additional treatment for bipolar symptoms, especially when standard treatments are not effective. It is used as an adjunctive therapy, meaning it is added to existing treatments, and may help with symptoms like mania and depression. ^{1 3 5 9 10}

Research Team

James J Prisciandaro, PhD

Principal Investigator

Medical University of South Carolina

Eligibility Criteria

Adults aged 18-65 with bipolar disorder and moderate to severe cannabis use disorder, who are already on mood stabilizers, can join this study. They must be willing to take medication and attend follow-ups. Exclusions include certain medical conditions, recent electroconvulsive therapy, pregnancy or inadequate contraception use, high risk of suicide or homicide, past negative reactions to gabapentin or MRI scans.

Inclusion Criteria

I take a daily mood stabilizer like lithium or lamotrigine.

I have a significant problem with cannabis use, tested positive for it, and it's my main substance issue.

I am willing to follow the treatment and check-up plan.

Exclusion Criteria

I am not pregnant, breastfeeding, and I use effective birth control.

My kidney function is low, with creatinine levels more than double the normal range.

I am not taking opioids, benzodiazepines, barbiturates, or similar medications.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive either Gabapentin or a matched placebo for 17 days. Study visits include MRI brain imaging scans, questionnaires, and clinical interviews.

2.5 weeks

5 visits (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

4 weeks

Treatment Details

Interventions

• Gabapentin
• Placebo

Trial Overview The trial is testing Gabapentin against a placebo in people with bipolar disorder who also smoke marijuana. Over 17 days, participants will take the assigned treatment and undergo brain scans (MRI), questionnaires, interviews, and side effect monitoring during five visits.

Participant Groups

Group I: Group A - Gabapentin Experimental Treatment 1 Intervention

Group II: Group B - Placebo Placebo Group 1 Intervention

Gabapentin is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Neurontin for:

• Postherpetic neuralgia
• Partial-onset seizures

Approved in European Union as Gabapentin for:

• Peripheral neuropathic pain
• Partial-onset seizures

Approved in Canada as Gabapentin for:

• Postherpetic neuralgia
• Partial-onset seizures

Who Is Running the Clinical Trial?

Medical University of South Carolina

Lead Sponsor

Trials

994

Recruited

7,408,000+

National Institute on Drug Abuse (NIDA)

Collaborator

Trials

2,658

Recruited

3,409,000+

Findings from Research

In a 1-year randomized controlled trial involving 25 euthymic bipolar disorder patients, gabapentin showed a statistically significant improvement in the Clinical Global Impressions scale for Bipolar Illness compared to placebo, indicating potential long-term benefits for managing bipolar disorder.

Gabapentin was well tolerated with no emergence of manic or depressive symptoms, suggesting it may be a safe adjunctive treatment option for patients already on mood stabilizers.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A double-blind, randomized, placebo-controlled, prophylaxis study of adjunctive gabapentin for bipolar disorder. Vieta, E., Manuel Goikolea, J., Martínez-Arán, A., et al.[2019]

Gabapentin has been reviewed for its effectiveness in treating bipolar disorder, but the evidence suggests it is not a suitable treatment option.

Further research is needed to explore any potential role gabapentin may have in managing bipolar disorder, as current data does not support its use.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin treatment for bipolar disorders. Maidment, ID.[2018]

In a double-blind, placebo-controlled trial involving patients with bipolar disorder, gabapentin did not show significant efficacy as an adjunctive treatment compared to placebo, with a smaller reduction in mania symptoms as measured by the Young Mania Rating Scale (YMRS).

The study indicated that more patients in the placebo group had adjustments made to their ongoing lithium therapy, suggesting that gabapentin may not be effective in managing bipolar disorder symptoms when added to standard treatments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin in bipolar disorder: a placebo-controlled trial of adjunctive therapy. Gabapentin Bipolar Disorder Study Group. Pande, AC., Crockatt, JG., Janney, CA., et al.[2019]

Gabapentin showed moderate effectiveness in treating depressive symptoms in patients with non-refractory bipolar disorder, with a 27.6% overall improvement in depression and a 57.5% improvement in a subgroup of depressed patients.

While gabapentin did not induce mania and was well-tolerated by most, 62% of patients experienced side effects, primarily sedation and nausea, leading to a 14% discontinuation rate due to adverse events.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin treatment of the non-refractory bipolar spectrum: an open case series. Ghaemi, SN., Goodwin, FK.[2019]

In a study of seven severe bipolar patients who could not use traditional mood stabilizers, gabapentin was administered for a median of 9 months, showing improvements in irritability and dysphoria for all patients.

However, the monthly relapse rate increased from 0.18 to 0.29 during gabapentin treatment, suggesting that while it may help with some symptoms, its overall effectiveness in preventing relapses needs further investigation through clinical trials.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Efficacy of gabapentin in a sample of bipolar patients]. Montañés Rada, F., de Lucas Taracena, MT.[2018]

Gabapentin, an anticonvulsant with a good safety profile, was successfully used to treat a 12-year-old boy with bipolar disorder II and ADHD, showing significant mood stabilization within 3 weeks and maintained improvement over 6 months.

Despite promising results in this case, there is a lack of controlled studies on gabapentin's efficacy for bipolar disorder in children and adolescents, highlighting the need for further research to explore its potential mood-stabilizing properties.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin and methylphenidate treatment of a preadolescent with attention deficit hyperactivity disorder and bipolar disorder. Hamrin, V., Bailey, K.[2018]

A literature review identified 29 studies on gabapentin for bipolar disorder, but most were of poor quality, including 15 uncontrolled case series and only 4 small randomized trials showing little evidence of efficacy.

Despite the lack of strong clinical evidence, the high volume of publications may have created a misleading perception of gabapentin's effectiveness, contributing to its widespread use in treating bipolar disorder.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin in the treatment of mental illness: the echo chamber of the case series. Carey, TS., Williams, JW., Oldham, JM., et al.[2018]

Gabapentin shows promise as a treatment for various psychiatric disorders, including bipolar disorder and anxiety, due to its favorable side effect profile and minimal drug interactions, but there is a lack of robust studies to confirm its efficacy as a standalone treatment.

Current evidence is limited to case reports and small studies, indicating that while gabapentin may be beneficial as an adjunct therapy, more well-designed research is needed to establish its effectiveness in treating bipolar disorder and anxiety disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin: a review of published experience in the treatment of bipolar disorder and other psychiatric conditions. Letterman, L., Markowitz, JS.[2019]

In a 12-week open trial with 22 patients suffering from bipolar depression, gabapentin (GBP) significantly reduced depression scores by 53%, indicating its potential effectiveness as an adjunctive treatment.

GBP was well tolerated among participants, with 55% showing moderate to marked improvement, particularly in those with mild to moderate depression, suggesting it may be a beneficial option for this subgroup.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin augmentation therapy in bipolar depression. Wang, PW., Santosa, C., Schumacher, M., et al.[2019]

In a study of 28 bipolar patients, gabapentin showed a positive response rate of 78% for those experiencing manic symptoms, with the fastest response seen in patients with hypomania (average 12.7 days).

Gabapentin was well tolerated, with sedation being the most common side effect, suggesting it could be a safe adjunctive treatment for refractory bipolar disorder, although further double-blind studies are needed to confirm its efficacy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Gabapentin in the acute treatment of refractory bipolar disorder. Altshuler, LL., Keck, PE., McElroy, SL., et al.[2019]

References

1. United States pubmed.ncbi.nlm.nih.gov

A double-blind, randomized, placebo-controlled, prophylaxis study of adjunctive gabapentin for bipolar disorder. [2019]

2. United States pubmed.ncbi.nlm.nih.gov

Gabapentin treatment for bipolar disorders. [2018]

3. Denmark pubmed.ncbi.nlm.nih.gov

Gabapentin in bipolar disorder: a placebo-controlled trial of adjunctive therapy. Gabapentin Bipolar Disorder Study Group. [2019]

4. Netherlands pubmed.ncbi.nlm.nih.gov

Gabapentin treatment of the non-refractory bipolar spectrum: an open case series. [2019]

5. Spain pubmed.ncbi.nlm.nih.gov

[Efficacy of gabapentin in a sample of bipolar patients]. [2018]

6. United States pubmed.ncbi.nlm.nih.gov

Gabapentin and methylphenidate treatment of a preadolescent with attention deficit hyperactivity disorder and bipolar disorder. [2018]

7. United States pubmed.ncbi.nlm.nih.gov

Gabapentin in the treatment of mental illness: the echo chamber of the case series. [2018]

8. United States pubmed.ncbi.nlm.nih.gov

Gabapentin: a review of published experience in the treatment of bipolar disorder and other psychiatric conditions. [2019]

9. Denmark pubmed.ncbi.nlm.nih.gov

Gabapentin augmentation therapy in bipolar depression. [2019]

10. Denmark pubmed.ncbi.nlm.nih.gov

Gabapentin in the acute treatment of refractory bipolar disorder. [2019]