Abstract
Though betahistine is the most commonly prescribed drug for vertigo, there are a lot
of controversies on its efficacy as well as its proclaimed mechanism of action. There
are authentic studies that have shown it to be no different from a placebo in Ménière’s
disease. It is often promoted as a vestibular stimulant, but scientific evidence suggests
that it is a vestibular suppressant. It is also not very clear whether it is an H3-receptor antagonist as most promotional literature shows it to be, or whether it
is an inverse agonist of the H3 receptors. Owing to insufficient data on its efficacy
in Ménière’s disease, betahistine is not approved by the U.S. Food and Drug Administration
(FDA). The much-advertised role of betahistine in augmenting histaminergic transmission
and thereby inducing arousal, though beneficial is some ways in the restoration of
balance after peripheral vestibulopathy, is yet not without systemic problems, and
the pros and cons of histaminergic stimulation in the brain need to be assessed more
by clinical studies in humans before imbibing it in clinical practice. The effect
of increasing blood flow to the cochlea and the vestibular labyrinth and “rebalancing
the vestibular nuclei” (as claimed in some literature) and whether they are actually
beneficial to the patient with vertigo in the therapeutic doses are very controversial
issues. The mechanism of action of betahistine in vertigo in general and in Ménière’s
disease in particular is very confusing, and there are too many conjectural and hypothetical,
if not controversial issues involved that call for close scrutiny. Everything taken
together, betahistine appears to be an unduly hyped-up drug and clinicians need to
review the scientific literature available and be convinced about its efficacy and
mechanism of action before using it in clinical practice. This review article puts
forth some controversial issues and reviews the relevant scientific literature for
clinicians to analyze and then take the final call on its clinical use.
Keywords
betahistine - treatment of vertigo - H
3-receptor - treatment of Ménière’s disease - betahistine in Ménière’s disease
