What is the maximum recommended daily dose of betahistine for adults with Ménière’s disease or vertigo, and how should it be adjusted for elderly patients or those with renal or hepatic impairment?

Maximum Dose of Betahistine

The standard maximum dose of betahistine is 48 mg daily (24 mg twice daily or as a single modified-release formulation), though higher doses up to 144 mg/day have been studied without demonstrating additional benefit, and exceptional cases have used 288-480 mg/day for severe refractory Ménière's disease. 1, 2

Standard Dosing Recommendations

For adults with Ménière's disease or vertigo, the recommended maximum daily dose is 48 mg, administered either as 24 mg twice daily or as a single 48 mg modified-release tablet. 1, 3, 2 This dosing is based on the American Academy of Otolaryngology-Head and Neck Surgery guidelines and represents the standard therapeutic approach. 1

• Treatment should continue for at least 3 months to properly evaluate efficacy, with reassessment at 6-9 months. 1, 2
• If no improvement occurs after 6-9 months, betahistine should be discontinued as continued therapy is unlikely to provide benefit. 1, 2

Higher Dose Evidence

Higher doses of 144 mg/day showed no advantage over the standard 48 mg/day dose in high-quality trials, including the BEMED trial which found no significant difference between betahistine at any dose and placebo in reducing vertigo attacks over 9 months. 1, 2

However, exceptional cases of severe refractory Ménière's disease have been treated with 288-480 mg/day in observational studies:

• In 11 patients who failed to respond to 144 mg/day, doses between 288-480 mg/day significantly reduced vertigo frequency and severity. 4
• Side effects at these ultra-high doses were mild, self-limiting, and did not require treatment discontinuation. 4
• This approach should only be considered in severe cases unresponsive to standard dosing and represents off-guideline use. 4

Dose Adjustments for Special Populations

No specific dose adjustments are recommended for elderly patients or those with renal or hepatic impairment based on current guidelines. 3 The American Academy of Otolaryngology-Head and Neck Surgery notes that routine laboratory monitoring is unnecessary because betahistine has demonstrated an excellent safety record over four decades, and guidelines advise against automatically excluding patients with comorbid renal or cardiac disease. 3

Safety Considerations and Contraindications

Absolute contraindication:

• Pheochromocytoma 1, 3, 2

Relative contraindications (use with caution):

• Active asthma 1, 3, 2
• Active peptic ulcer disease 1, 3, 2

Common side effects include:

• Headache, balance disorder, nausea, upper gastrointestinal symptoms, nasopharyngitis, feeling hot, eye irritation, and palpitations. 1, 3, 2
• No routine laboratory monitoring is required. 1, 3

Important Clinical Caveats

The evidence for betahistine efficacy is conflicting. The American Academy of Otolaryngology-Head and Neck Surgery explicitly states they cannot make a definitive recommendation for betahistine use in controlling Ménière's disease symptoms due to conflicting evidence from high-quality trials. 1, 2 The most recent high-quality BEMED trial found no significant difference between betahistine and placebo. 1, 2

Despite this, betahistine remains widely used based on:

• Older observational studies suggesting benefit 5, 6, 7
• Over 40 years of clinical experience with an excellent safety profile 5
• Potential benefit when combined with intratympanic steroids (73% improvement vs 44% without betahistine) 1, 2

For refractory cases, consider intratympanic gentamicin (70-87% complete vertigo control) or intratympanic steroids (85-90% improvement) rather than escalating betahistine doses beyond 48 mg/day. 1, 2