What is the recommended dose of betahistine (histamine receptor agonist) for treating vertigo?

Recommended Dosage of Betahistine for Vertigo Treatment

The recommended dosage of betahistine for treating vertigo is 48 mg daily, administered for at least 3 months, though this has not shown significant benefit over placebo in the most recent high-quality trials for Ménière's disease. 1, 2

Dosage Recommendations and Evidence

• The standard dosage of betahistine for vertigo treatment is 48 mg daily, typically divided into three doses of 16 mg each 2
• Higher doses of betahistine (144 mg/day) have been studied but did not show significant improvement in vertigo control compared to lower doses (48 mg/day) or placebo in the BEMED trial 1
• Treatment duration should typically be at least 3 months to evaluate efficacy, though most betahistine studies covered only 2-12 weeks 1, 2
• The BEMED trial, which is considered the highest quality evidence available, found that neither low-dose (48 mg/day) nor high-dose (144 mg/day) betahistine for 9 months changed the mean number of vertigo attacks compared to placebo in Ménière's disease patients 1

Clinical Considerations and Contraindications

• Betahistine is completely contraindicated in patients with pheochromocytoma 3
• It should be used with caution in patients with asthma and history of peptic ulcer disease 1, 3
• Common side effects include headache, balance disorder, nausea, nasopharyngitis, feeling hot, eye irritation, palpitations, and upper gastrointestinal symptoms 1
• The American Academy of Otolaryngology-Head and Neck Surgery does not make a definitive recommendation for betahistine use in controlling Ménière's disease symptoms due to conflicting evidence 1

Alternative Dosing Strategies

• Some clinicians have used much higher doses of betahistine (216-1920 mg/day, mean 895.4 mg/day) for treatment of Ménière's disease, though this is not supported by clinical guidelines 4
• A combination approach using betahistine with the MAO-B inhibitor selegiline (5 mg/day) may allow for lower betahistine doses (mean 204.9 mg/day) while maintaining efficacy, as MAO-B inhibition reduces betahistine's first-pass metabolism 4
• For acute vertigo episodes, medications with direct antiemetic and anti-vertigo effects like prochlorperazine are preferred over betahistine, which works through vascular mechanisms 5

Monitoring and Duration

• If oral betahistine is initiated, patients should be reassessed regularly for improvement or stabilization of symptoms and to monitor for medication intolerance or side effects 1
• Clinicians should discuss with patients about titrating down or stopping the medication once symptoms subside 1
• If there is no improvement in vertigo symptoms after 6-9 months of treatment, it is unlikely that continued betahistine therapy will be beneficial 1, 5

Important Caveats

• Despite decades of clinical use and earlier positive meta-analyses, the most recent high-quality evidence (BEMED trial) suggests betahistine may not be more effective than placebo for Ménière's disease 1
• Patients who stop betahistine therapy after experiencing benefit may experience recurrence of symptoms within 2-4 weeks 4
• The efficacy of betahistine in central vestibular disorders is under-researched and requires further investigation 6