CHAMGAP
APPROVEDReviewed and approved by the Chamgap Editorial Team (2026-07-24). The draft was written by AI, the existence of all 2 cited sources was verified at the original page, and the verdict passed blind grading and adversarial audit. Methodology v0.6.
Verdict No. 1859 · Search date 2026-07-24 · Methodology v0.6

Gabapentin,
does it really help with Prevention of attack frequency in adult episodic migraine?

30-Second Summary
D
Evidence Grade D · 30 · Safety caution
Unlike the selected positive publication, the complete trial set is null, but uncertainty is too wide for F
Dizziness, somnolence, ataxia, and peripheral edema are common and can increase driving and fall risk. Opioids or other central nervous system depressants, respiratory disease, and older age require monitoring for respiratory depression, and abrupt discontinuation should be avoided.
What the
research shows
Gabapentin is rated D because the Cochrane review combining published and unpublished trials found no significant reduction in episodic-migraine frequency. Across four trials and 351 participants, monthly headache frequency MD was -0.44 (95% CI -1.43 to 0.56), which was null but still included benefit exceeding one attack per month, so meaningful benefit was not excluded and F is unwarranted.
What the
ads claim
Use for neuropathic pain and other neurologic symptoms is generalized into migraine prevention, or only the selected positive publication is cited. Evidence from another indication for the same drug is not preventive-migraine evidence.
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Useful facts when choosing a product

  • RR995-00085 randomized 157, treated 143 under double masking, and included 122 in the prespecified efficacy analysis, so enrollment and actual analysis counts differed.
  • Cochrane included three confidential manufacturer reports released through litigation, correcting the bias from published evidence alone.
Gap Measurement · Verdict 1859 · D 30
What advertising claims
What independent, higher-quality research supports
△ GAP
01

What the research actually shows

RR995-00085 was a separate unpublished Parke-Davis trial: 157 randomized, 143 treated, and 122 analyzed for frequency, with a null result. Mathew 2001 was not RR995-00085; it published the distinct RR995-00074 trial, whose frequency analysis of 113 participants gave MD -0.80 (95% CI -1.55 to -0.05), the only positive result among five gabapentin trials. Three other trials were null. Linde 2013 reviewed six gabapentin or gabapentin-enacarbil trials and 1,009 participants. The four-trial, 351-participant gabapentin frequency synthesis was null, MD -0.44 (95% CI -1.43 to 0.56), P=0.39. This gives R0 and C0 because the interval retains a reduction of 1.43 attacks. Verdicts 780, 1682, and 1136 concern other indications and were not transferred. Verdict 1850 for episodic botulinum toxin is F with 10 points because axis 5 is C1 and excludes benefit; gabapentin remains D because its C0 interval leaves meaningful benefit possible.

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Why this is classified as D (30)

P, R0, I1, E0, B1, and C0 derive D with 30 points. Some trials were positive and others null, individual trials were small, and pooled intervals did not exclude meaningful benefit.

Counterpoint. Preventive decisions should compare options with direct positive evidence, including topiramate. A person already taking gabapentin should not stop abruptly and should discuss tapering with the prescriber.

Rejudgment record. Cross-check applied — Applied the null Cochrane synthesis including unpublished company reports while assigning C0 because the monthly headache-frequency interval retained clinically meaningful benefit

Scoring profile behind this grade
EndpointPPatient-reported treatment goal - the symptom is the goal
ReplicationR0Trials conflict in direction
IndependenceI1Mixed funding sources
Effect sizeE0Null
PrecisionC0The confidence interval leaves room for benefit

The scoring table and the verdict agree (D).

Sub-claim grades by effect

This ingredient is marketed for several effects. A single overall grade blends strong and weak claims together, so each effect is graded separately here. The overall grade reflects the strongest disconfirming or core claim.

Effect (sub-claim)GradeBasis
Reduction in monthly headache frequencyDFour trials and 351 participants gave a null MD of -0.44 (-1.43 to 0.56).
At least 50% migraine-frequency responseDTwo trials and 235 participants gave a nonsignificant OR of 1.59 (0.57 to 4.46).
Reduction in 28-day migraine attack frequencyDThe prespecified analysis in the key company report failed primary efficacy with a between-group difference of +0.50 attacks.

Cross-check — Codex and Claude

This verdict was drafted by Codex through literature review and source-existence checks, cross-checked through blind grading and adversarial audit, and settled by reapplying the methodology boundary rules. Cases with split grades were resolved through rejudgment.
03

Evidence Table

StudyDesignSampleFundingEndpointResultWeight
Study 1Separate randomized double-blind placebo-controlled manufacturer trial122Manufacturer trial by Parke-Davis with an employee coauthorTwenty-eight-day headache frequencyNull frequency result in 122 analyzed participantsUnpublished null trial distinct from Mathew 2001
Mathew NT et al. RR995-00074, 2001Separate multicenter randomized double-blind placebo-controlled trial113Manufacturer trial by Parke-Davis with an employee coauthorMonthly headache frequencyMD -0.80 (95% CI -1.55 to -0.05); the only positive result among five trialsPositive trial distinct from RR995-00085
Linde M et al. Cochrane review. 2013Systematic review and meta-analysis of randomized and quasi-randomized trials235Academic Cochrane review; included evidence mixed manufacturer and nonmanufacturer sourcesMonthly headache frequency and at least 50% responseFrequency MD -0.44 (-1.43 to 0.56), P=0.39; response OR 1.59 (0.57 to 4.46), P=0.38Decisive synthesis for E0 effect and C0 precision
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Receipt — 2 References

All 2 cited sources were verified for existence at the original page (as of 2026-07-24).

Mathew NT, Rapoport A, Saper J, et al. Efficacy of gabapentin in migraine prophylaxis. Headache. 2001;41(2):119-128. PMID: 11251695. DOI: 10.1046/j.1526-4610.2001.111006119.x.
checked
Linde M, Mulleners WM, Chronicle EP, McCrory DC. Gabapentin or pregabalin for the prophylaxis of episodic migraine in adults. Cochrane Database Syst Rev. 2013;2013(6):CD010609. PMID: 23797675. PMCID: PMC6599858. DOI: 10.1002/14651858.CD010609.
checked
Draft and rewrite: Codex (AI) · Verification: Codex blind grading and adversarial audit · Final adjudication: Claude
Reviewed and approved: Chamgap Editorial Team · Approval date: 2026-07-24 · Corrections: none

Cite this verdict

Gabapentin x episodic migraine prevention Evidence Grade D card
[Chamgap] Gabapentin x episodic migraine prevention — Evidence Grade D·30. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/cognition/gabapentin-episodic-migraine-prevention/ · CC BY 4.0

CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.

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What this document does and does not do

Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.