Betahistine is a weak agonist of the H1 receptor, which can promote wakefulness by activating the H1 receptor, and also has a vasodilatory effect on cerebral blood vessels to increase cerebral blood flow. Betahistine is also a strong antagonist of the H3 receptor, which can increase the synthesis and release of histamine through antagonism of the H3 autoreceptor. Multiple animal studies have shown that betahistine mesylate can increase cerebral blood flow and improve the dizziness symptoms of patients with vascular vertigo/dizziness. A dosage regimen of 12 mg per dose, three times a day, has better efficacy.