What are the diagnostic criteria and treatment recommendations for vertebrobasilar migraines?

Vertebrobasilar Migraine: Diagnostic Criteria and Treatment

Critical Clarification

The term "vertebrobasilar migraine" is outdated and has been replaced by "vestibular migraine" in current diagnostic nomenclature. The older terminology implied a vascular mechanism that has not been substantiated, and modern classification systems no longer use this term 1.

Diagnostic Criteria

Vestibular migraine requires ≥5 episodes of vestibular symptoms lasting 5 minutes to 72 hours, with a current or past history of migraine. 1

Essential Diagnostic Elements:

• Episode frequency: At least 5 documented attacks 1
• Duration: Vestibular symptoms must persist between 5 minutes and 72 hours per episode 1
• Vestibular symptoms: Include spontaneous vertigo, positional vertigo, visually-induced vertigo, head motion-induced vertigo, or head motion-induced dizziness with nausea 1
• Migraine features: Must meet criteria for migraine with or without aura, either during the vestibular episode or in the patient's history 1

Critical Exclusions:

• Rule out central causes: Stroke and multiple sclerosis must be excluded through appropriate neuroimaging and clinical evaluation 1
• Distinguish from peripheral causes: Benign paroxysmal positional vertigo (BPPV), Ménière's disease, and vestibular neuritis require differentiation 1

Treatment Algorithm

Step 1: Lifestyle Modifications (First-Line for All Patients)

Dietary and lifestyle interventions should be implemented before or alongside pharmacological therapy. 1

• Dietary restrictions: Limit salt/sodium intake, avoid excessive caffeine, alcohol, and nicotine 1
• Metabolic optimization: Eat well-balanced meals, maintain adequate hydration 1
• Sleep hygiene: Establish regular sleep patterns with consistent bedtime and wake times 1
• Stress management: Implement stress reduction techniques and regular exercise 1
• Trigger identification: Identify and manage allergies and other personal triggers 1

Step 2: Acute Attack Management

For acute vestibular attacks, use antiemetic medications such as diphenhydramine or meclizine, but avoid long-term vestibular suppressant use. 1, 2

• Antiemetics: Diphenhydramine, meclizine, or metoclopramide for symptom relief during attacks 1, 2
• Vestibular suppressants: Scopolamine can suppress acute vertigo but has significant side effects; benzodiazepines may help but carry dependency risk 1
• Triptans: Can treat concurrent headache during vestibular migraine attacks 1
• Critical pitfall: Do not use vestibular suppressants for long-term management 1

Step 3: Preventive Pharmacotherapy (When Symptoms Occur ≥2 Days/Month)

Initiate preventive therapy when attacks occur ≥2 days per month despite optimized acute treatment. 1

First-Line Preventive Agents:

Beta-blockers are first-line preventive medications, particularly in patients with comorbid hypertension. 1

• Propranolol: 80-240 mg/day 1, 3
• Metoprolol, atenolol, or bisoprolol: Alternative beta-blockers 1, 3
• Contraindication: Avoid in patients with asthma 3

Topiramate 50-100 mg oral daily is first-line, especially beneficial in obese patients. 1

Candesartan (angiotensin receptor blocker) is a first-line option. 1

Second-Line Preventive Agents:

Tricyclic antidepressants are particularly useful for patients with coexisting anxiety or depression. 1

• Amitriptyline: 10-100 mg oral at night, or 30-150 mg/day 1, 3
• Nortriptyline: Alternative tricyclic 1, 3

Flunarizine 5-10 mg oral once daily for patients who fail first-line agents. 1

• Contraindication: Avoid in patients with Parkinsonism or depression 1

Valproic acid 600-1,500 mg oral once daily for men only. 1

• Absolute contraindication: Women of childbearing potential due to teratogenicity 1, 4

Lamotrigine is preferred when vertigo is more frequent than headaches. 3

Third-Line Preventive Agents (Refractory Cases):

CGRP monoclonal antibodies should be considered for patients who have failed first- and second-line agents. 1

• Erenumab: 70 or 140 mg subcutaneous once monthly 1
• Fremanezumab: 225 mg subcutaneous once monthly or 675 mg quarterly 1
• Galcanezumab: Per standard dosing 1
• Eptinezumab: 100 or 300 mg intravenous quarterly 1

OnabotulinumtoxinA 155-195 units to 31-39 sites every 12 weeks for chronic migraine with vestibular symptoms. 1

Step 4: Non-Pharmacological Adjuncts

Biobehavioral therapy can be as effective as pharmacological approaches and should be combined with medication. 1

• Relaxation techniques: Stress management and biofeedback 1, 2
• Vestibular rehabilitation: Useful when complications include loss of confidence in balance or visual dependence 3
• Neuromodulatory devices: Consider as adjuncts when medication is contraindicated 1
• Acupuncture: Has some supporting evidence though not superior to sham 1

Treatment Assessment and Duration

Assess efficacy of oral preventive medications after 2-3 months at therapeutic dose. 1

• Oral medications: Evaluate response at 2-3 months 1
• CGRP monoclonal antibodies: Assess efficacy after 3-6 months 1
• OnabotulinumtoxinA: Assess efficacy after 6-9 months 1
• Treatment pause: Consider pausing after 6-12 months of successful control to determine if preventive therapy can be stopped 1

Critical Pitfalls to Avoid

Never use oral ergot alkaloids, opioids, or barbiturates due to questionable efficacy with considerable adverse effects and dependency risk. 1

Avoid overuse of acute medications, which risks medication overuse headache. 1

Do not abandon treatment prematurely—efficacy takes weeks to months to establish. 1

Set realistic expectations that efficacy is rarely observed immediately and may take several weeks to months. 1

Failure of one preventive treatment does not predict failure of other drug classes. 1