The mechanism of action of betagistin is known only in part. There are several possible hypotheses, confirmed by preclinical and clinical data:
- Influence on gistaminergic system
Partial agonist H1-gistaminovyh and antagonist H3-gistaminovyh receptors of vestibular nuclei of the central nervous system, has insignificant activity in relation to H2receptors. Betagistin increases histamine metabolism and its release by blocking presynaptic H3-receptors and decrease in the number of H3receptors.
- Increased blood flow of the cochlear region, as well as the entire brain
According to preclinical studies betagistin improves blood circulation in the vascular stria of the inner ear by relaxing precapillary sphincters of the vessels of the inner ear. It is also shown that betagistin increases the blood flow of the brain in humans.
- Facilitating the process of central vestibular compensation
Betagistin accelerates the recovery of vestibular function in animals after unilateral vestibular neurectomy, speeding up and facilitating central vestibular compensation due to antagonism with H3-histamine receptors.
The recovery time after vestibular neurectomy in humans in the treatment with betahistine is also reduced.
- Excitation of neurons in the vestibular nuclei
It dose-dependently reduces the generation of action potentials in the neurons of the lateral and medial vestibular nuclei.
Pharmacodynamic properties found on animals provide a positive therapeutic effect of betahistine in the vestibular system.
The efficacy of betahistine was demonstrated in patients with vestibular dizziness and Menier's syndrome, which was manifested by a decrease in the severity and frequency of dizziness.