Vertigo and its treatment with Betahistine

Index

What is vertigo. Symptoms of vertigo. Causes of vertigo. Complications of vertigo. Current therapies of Vertigo. Betahistine. Indications of Betahistine in details Mode of action of Betahistine. Your words.

INTRODUCTION

25 % of population will experience dizziness , with or without vertigo at some point of their life.

Older people experience more frequently that younger one. All vertigo comes with dizziness , but reverse is not true.

What is Dizziness

Feeling of light-headedness due to Anxiety / Panic disorder / Mood disorder Cardiovascular problem Medications like sedative , hypnotics etc. Problems with the chemical changes within the body like

hypoglycemia

Symptoms of dizziness

Light-headedness.

Motion sickness or nausea.

Faintness or weakness

What is vertigo

>Vertigo is a strong feeling of movement or spinning when you are actually still.

>It may also worsen and make you vomit .

>These episodes of vertigo are not constant.

Symptoms of vertigo

Sense of movement of yourself and objects around you . An illusion of spinning and circling . Worsened with head movements. Episodes come and go . Nausea and vomiting . Ringing in the ears .

CAUSES

Motion sickness . Abnormality in the inner ear . Central &peripheral vestibular disorders . Menieres disease. Labrinthitis

Current Therapies for Vertigo

Life style changes (low salt ). Anticolinergics (does not cross BBB) Antihistamines Benzodiazepines (addiction) Antiemetics (side effects like restless ness ,EPS prostrate

enlargement, drowsiness.) Diphenhydramine (Benadryl) Anti emetics and Anti vertigo agent-Betahistine

Description

Betahistine dihydrochloride is a white crystalline powder and very hygroscopic in nature .

Composition : 16mg &24mg tablets contain 16mg and 24mg Betahistine dihydrochloride respectively .

A histamine H 1-agonist with an intrinsic activity equal to that of histamine and an H 1-agonistic activity of about 0.07 times that of histamine – Not affect wakefulness

A potent H 3-receptor antagonist – Effective in central and peripheral vestibular disorders

Histavert exhibits H1 Agonistic and H3 Receptor antagonistic action .

H1receptor activation stimulates the release histamine Betahistine when acts as agonist at H1receptor it increases the

release of histamine . (histamine release causes vasodilatation in the blood vessels .)

Mode of Action

Betahistine

Betahistine when acts as H3antagonist(H3 receptors controls histamine release .

Antagonist activity causes histamine release .That means because of H1 Agonistic activity&H3 antagonist activity

there is vasodialation .

Histamine is an amine. It regulates physiological functions and also acts as neurotransmitter. Histamine is stored in mast cells . Mast cells are present all internal body surfaces and blood vessels .

Histamine exerts its action by combining with specific receptors . There are four histamine receptors . H1 Receptors – present in smooth muscle .endothelium ,CNS . H2 Receptors – present in parietal cells , H3 Receptors – present in brain and peripheral regions .

Agonist – It is substance that binds to the receptor and triggers the response .

Antagonist- it is substance that inhibits the normal function of the receptors .

PHARMACOKINETICS

Rapidly and completely absorbed from the GI tract Metabolized to primary metabolite-2-pyridylacetic acid Plasma half life : 3.4 hours 90 % of the orally administered excreted within 24 hours through

urine

INDICATIONS

Menieres Disease Benign Paroxysmal Positional Vertigo Peripheral Vestibular Vertigo Labrynthitis Tinnitus

Inner ear

 

 

Ménière’s disease

Ménière’s disease is one of the most common causes of dizziness originating in the inner ear due to abnormality in the fluids in the inner ear .

Benign Paroxysmal Positional Vertigo

Benign Paroxysmal Positional Vertigo (BPPV) is an inner ear problem that results in short lasting, but severe, room-spinning vertigo.

Peripheral Vestibular Vertigo

If vertigo results from a disorder in the peripheral vestibular system (i.e., structures of the inner ear).

It also may occur due a disorder in the central vestibular system (i.e., vestibular nerve, brainstem, and cerebellum). In some cases, cause is unknown.

Labyrinthitis

Labyrinthitis is an inflammation of labyrinth (a system of intercommunicating cavities and canals in the inner ear).

The syndrome is defined by the acute onset of vertigo, commonly associated with head or body movement.

Tinnitus

It is the perception of sound in the ear when no external source is present .

Dosage and Administration

>24 - 48 mg administered orally in divided doses.

CONTRAINDICATION

Patients hypersensitive to Betahistidine Patients with Peptic Ulcer Patients with pheochromocytoma`(tumor in the adrenal

medulla ,increased secretions of neurotransmitters )