Overview
Betahistine is a histamine analog used primarily for the symptomatic treatment of vertigo associated with Ménière's disease. It acts as a partial agonist at histamine H1 receptors and an antagonist at H3 receptors, improving vestibular blood flow and reducing endolymphatic pressure.
Mechanism of Action
Partial agonist at histamine H1 receptors in the inner ear, improving microvascular circulation in the stria vascularis. Antagonist at presynaptic histamine H3 receptors, increasing histamine release and neurotransmission in vestibular nuclei. This dual action helps reduce endolymphatic pressure and improve vestibular compensation.
Indications
- Symptomatic treatment of vertigo associated with Ménière's disease
- Management of vestibular vertigo
Dosage
Typically 8-16 mg three times daily. Maximum daily dose: 48 mg. Should be taken with meals to reduce gastrointestinal side effects. Treatment duration depends on clinical response.
Contraindications
- Hypersensitivity to betahistine or any component of the formulation
- Active peptic ulcer
- Pheochromocytoma
Side Effects
- Headache
- Nausea
- Dyspepsia
- Abdominal discomfort
- Drowsiness
- Rash
- Pruritus
- Flushing
Interactions
- Antihistamines may reduce therapeutic effect
- Monoamine oxidase inhibitors (MAOIs) - theoretical risk of hypertensive crisis
- Increased risk of sedation with CNS depressants