Is gabapentin (anticonvulsant) effective for migraine prevention?

Gabapentin for Migraine Prevention

Gabapentin is not a first-line medication for migraine prevention, as it has only fair evidence of effectiveness compared to the strongly recommended first-line agents. 1, 2

Evidence-Based Preventive Treatment Options

First-Line Medications (Strong Evidence)

According to the American Academy of Neurology and migraine treatment guidelines, the following medications have strong evidence for migraine prevention:

• Beta-blockers:
  • Propranolol (80-240 mg/day)
  • Timolol (20-30 mg/day)
• Antidepressants:
  • Amitriptyline (30-150 mg/day)
• Anticonvulsants:
  • Divalproex sodium (500-1500 mg/day)
  • Sodium valproate (800-1500 mg/day)
  • Topiramate (100 mg/day) 1

Second-Line Medications (Fair Evidence)

• Gabapentin (1200-2000 mg/day) 2
• Naproxen sodium 2
• Candesartan (16-32 mg/day) 1

Gabapentin's Efficacy in Migraine Prevention

While gabapentin is not a first-line agent, several studies have shown it may be effective:

• A 2002 prospective, open, multicenter study found gabapentin (1200-2000 mg/day) reduced:

  • Number of migraine attacks (from 5.3 to 2.2 attacks/month)
  • Pain intensity
  • Duration of pain
  • No significant differences were found between 1200 mg and 2000 mg doses 3

• A 2000 double-blind randomized placebo-controlled study using gabapentin 1200 mg/day showed significant reduction in frequency and intensity of migraine in 30 patients 4

• A 2009 observational study of 67 patients using gabapentin 900-1800 mg/day showed:

  • Reduction from 15.8 to 8.6 migraine days per 4 weeks
  • 55.7% of patients had 50% reduction in pain intensity
  • Significant reduction in acute medication use 5

Safety Profile and Adverse Effects

Gabapentin is generally well-tolerated but has notable side effects:

• Common adverse effects include:

  • Drowsiness (22.6%)
  • Asthenia (7.9%)
  • Dizziness (4.9%)
  • Abdominal pain (3.7%)
  • Dazedness (3.7%) 3

• In the 2009 study, adverse events were reported by 47.8% of patients, with 22.4% discontinuing the drug due to side effects 5

Clinical Decision Algorithm for Migraine Prevention

1. Start with first-line agents based on patient comorbidities:

   • Hypertension → Beta-blockers (propranolol, timolol)
   • Depression/anxiety → Amitriptyline
   • Epilepsy → Topiramate, divalproex sodium, sodium valproate

2. Consider gabapentin as a second-line option when:

   • First-line agents are contraindicated
   • Patient has failed multiple first-line therapies
   • Patient has comorbid neuropathic pain
   • Patient cannot tolerate side effects of first-line agents

3. When using gabapentin:

   • Start at 300 mg daily and titrate gradually
   • Target dose: 1200-1800 mg/day divided in three doses
   • Monitor for 4-6 weeks before assessing effectiveness
   • Continue effective treatment for 3-6 months before attempting discontinuation 1

Important Caveats

• Gabapentin should be used with caution in elderly patients and those with renal impairment
• Avoid abrupt discontinuation; taper gradually to prevent withdrawal symptoms
• Monitor for medication overuse headache by limiting acute medications to ≤15 days/month for NSAIDs and ≤10 days/month for triptans 1
• Valproate is contraindicated during pregnancy due to teratogenicity 1

Gabapentin may be particularly useful in patients with comorbid conditions such as neuropathic pain, anxiety disorders, or insomnia, where its mechanism of action could provide dual benefits.