Betahistine Mesylate

Betahistine Mesilate dilates precapiilary sphincters, increasing the blood flow in the inner ear. It controls the permeability of capillaries in the inner ear, thereby removes endolymphatic hydrops. It also improves cerebral circulation, increasing blood flow in the internal carotid artery. Thus, Betahistine Mesylate is clinically useful for the relief of vertigo and dizziness.

The mechanism of action of betahistine is known partially. Betahistine has a very strong affinity as an antagonist for histamine H3 receptors and a weak affinity as an agonist for histamine H1 receptors. The active ingredient is a specific histamine agonist with virtually no H2-activity.

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. It appears to act on the precapillary sphincter in the stria vascularis of the inner ear, thus reducing the pressure in the endolymphatic space.

In addition, betahistine has a powerful antagonistic effects at H3 receptors, and increases the levels of neurotransmitters released from the nerve endings. The increased amounts of histamine released from histaminergic nerve endings stimulates H1 receptors, thus augmenting the direct agonistic effects of betahistine on these receptors. This explains the potent vasodilatory effects of betahistine in the inner ear. This explains the efficacy of betahistine in the treatment of vertigo.

Usually for adults, administer orally 6 mg to 12 mg three times per day after meals. The dose may be adjusted according to the age of patient and severity of symptoms.

Hypersensitivity to betahistine mesylate, pheochromocytoma, peptic ulcer, acute bronchial asthma.

Nausea or vomiting may rarely occur. Hypersensitivity reactions, such as skin rash, may rarely occur.

Safety of Betahistine during pregnancy has not been established. This drug should be administered to pregnant patients or women suspected of being pregnant, only if the expected therapeutic benefit is thought to outweigh any possible risk.

Patients with a history of digestive ulcer or an active digestive ulcer, Patients with bronchial asthma, Patients with pheochromocytoma.

Drugs used in meniere's diseases

Store in cool and dry place. Protect from light & moisture.