Description
It is commonly prescribed for balance disorders or to alleviate vertigo symptoms associated with Meniere’s disease.
MODE OF ACTION
Betahistine has a very strong affinity as an antagonist for histamine H3 receptors and a weak affinity as an agonist for histamine H1 receptors. Betahistine seems to dilate the blood vessels within the inner ear which can relieve pressure from excess fluid and act on the smooth muscle.
Betahistine has two modes of action. Primarily, it has a direct stimulating (agonistic) effect on H1 receptors located on blood vessels in the inner ear. This gives rise to local vasodilation and increased permeability, which helps to reverse the underlying problem of endolymphatic hydrops.
More importantly, betahistine has a powerful antagonistic effect at H3 receptors, thereby increasing the levels of neurotransmitters histamine, acetylcholine, norepinephrine, serotonin, and GABA released from the nerve endings. The increased amounts of histamine released from histaminergic nerve endings can stimulate receptors. This stimulation explains the potent vasodilatory effects of betahistine in the inner ear.
CONTRAINDICATION
Betahistine is contraindicated for people with pheochromocytoma. People with bronchial asthma and history of peptic ulcer need to be closely monitored.
SIDE EFFECTS
- Low level of gastric side effects
- No significant antidopaminergic effects
- Nausea can be a side effect, but the patient is generally already experiencing nausea due to the vertigo so it goes
- largely unnoticed.
This should be administered strictly with the prescription and advise of medical practitioners only.
