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Fatthi Abdel Baki MD Alexandia Medical School Vertigo Pharmacotherapy Neurotransmitters Neurotransmitters Post synaptic neuron Post synaptic receptor Pre synaptic neuron

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Page 1: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Fatthi Abdel Baki MDAlexandia Medical School

VertigoPharmacotherapy

Neurotransmitters

Neurotransmitters

Post synaptic neuron

Post synaptic receptor

Pre synaptic neuron

Page 2: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Excitatory or Inhibitory

Glutamate:Excitatory

GABA (2):

Inhibitory

Main Neurotransmitters

Excitatory or Inhibitory

• Depends on type of receptors:

– Acetyl choline Nicotinic & Muscarinic (5)– Dopamine (5) D1 to D5– Histamine (3) H1; H2;H3– Serotonin 5 HT (7)– Nitric oxide

Other Neurotransmitters

Page 3: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Vestibular Lesion

Vestibular suppressants

Vestibular Stimulants

Management Plan

Acute Episode Speed recovery Target treatment

VertigoVomitingNystagmus

VasodilatorsRheologyOxygenationVestibular activity

MeniereVestibular neuritisVBIMigraineVascular loop

Vertigo

Page 4: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Vestibular suppressants

Vestibularactivity

GABA

HistamineGlutamateCalcium ion

GABA (A) agonist:Benzodiazepines

GABA (B) agonist: Baclofen

Antihistamine:MeclizineCalcium channel

blockerCinnarazine

VomitingCentre

GIT

CTZVestibular

NucleiDopaminergic

pathway

hist

amin

ergi

c

path

way

SerotoninSerotoninblockersblockers(5HT3)(5HT3)

antihistamines antihistamines (H1)(H1)

DopamineDopamineantagonist antagonist

(D2)(D2)

Metoclopramide(Primperan)

Ondansetron(Zofran)

Meclizine

Antiemetics

Sero

ten

erg

icp

ath

way

Page 5: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

RheologyRBC …

Poor tissuePerfusion &oxygenation

Inner ear vessel

Poor vestibular activity

Vasodilators

Vasoactive

Oxygenator

Vestibularstimulants

Histamine agonistsCalcium blockersPentoxyphyllineOxybralGinko

Buflomedil Calcium blockersPentoxyphylline

almitrine + raubasineBuflomedilVincaminevinpoctineHistamine agonists

PiribidilPiracetamGinko

Speed Recovery

vestibularSuppressant

Antiemetic

VasoDilator

Vasoactive

O 2 vestibularStimulant

Antihistamine + +

Benzodiazepam +

Cinnarazine + + +

Betahistine + +

Vicamine + +

almitrine + raubasine

+

Buflomidil + +

Pirebidil + +

Pentoxyphilline + +

Ginko + +

Drugs: mechanism of Action

Page 6: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Side Effects / Precautions

Antihistamine Sedation; anticholinergic; extrapyramidal

Benzodiazepam Sedation; habituation

Betahistine Bronchial asthma

Cinnarizine Sedation

Vincamine Hypotension

Almitrine + Raubasine

Drowsiness

Buflomedil GIT

Pirebidil GIT

Pentoxyphylline Flushing/headache

Drugs: Side effects

BetahistineBetaserc

• Widely used for the management of vertigo.• UK (Meniere’s): 94% betahistine; 63%

diuretics• Not approved by the FDA • Randomized controlled trial: controversial

– No EBM– Recent large study (144) showed

statistically significant improvement• Dose 16-32 mg three times/day for 2 to 40 w• Do not use with antihistamine

Page 7: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Beta-Histine

Action

Post-synaptic

Microcirculation ofinner ear and brain

Central activity vestibular nuclei

Vestibularcompensation

Pre

synaptic

H

H

H3

H

BH

HistaminergicNerve ending

Buflomedil HClLoftyl

RBC’s deformability

RBC’s aggregation

Platelet aggregation

Leukocytic adherence to vessel wall

Tissue Perfusion

Tissue Oxygenation

Page 8: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Alimintrine bismesylate / rabusineDuxil

Increases Oxygen availabilityIncreases Oxygen availability Increases Oxygen utilizationIncreases Oxygen utilization

VincamimeOxybral

• Increase cerebral flow

• Increase oxygen capture and utilization by the hypoxic neurons.

Page 9: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Dopamine agonistsPiribedil

•• Compensate deficient Dopaminergic Compensate deficient Dopaminergic neurotransmission (aging)neurotransmission (aging)

•• Reducing the sympathetic vasoReducing the sympathetic vaso--constrictingconstrictingtone.tone.

Ginko

• Reduces the viscosity of the blood

• Anti-oxidant.

• Enhance vestibular compensation in animals

Page 10: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Target treatment

• Meniere

• Vestibular neuritis

• VBI

• Migraine

Vertigo

Prophylaxis

• Vasodilators

• Diuretics and dietary salt restriction – in salt sensitive persons

• Glucocorticoids– in salt insensitive persons

• Chemical labyrinthectomy

Meniere

Page 11: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Vasodilators

• Betahistine (an oral histamine analogue)

• Role of Betahistine in Meniere disease:– No EBM

Meniere

Ions Homeostasis

VasopressinAldosterone

Page 12: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Ions HomeostasisMeniere

IncreaseVasopressinAldosterone

DiureticSteroids

Diuretics

• Potassium loosing diuretics (Thiazide) – Multiple undesirable side effects

• Potassium sparing diuretic (Spironolactone)– Homeostasis theory

• Combined (Thiazide+ Amiloride)• Role of diuretics in Meniere:

– No EBM

Meniere

Page 13: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Intra- tympanic steroids

Methyl prednisolone: solumederol

• Advantage:– Higher concentration in endolymph and perilymph

after administration

• Disadvantage:– Slow absorption from endolymph into stria. It remain

in endolymph longer than dexa by 6hs– Painful

Meniere

Intra- tympanic steroidsDexamethasone: (fortacorten)

• Advantage:– Faster absorption and diffusion from endolymph into

stria and surrounding tissue (steroid act intracellular)

• Disadvantage:– Need high concentration; 24mg /ml not available in

market

• Dose:– 24mg (compounding) /cc / week (2

treatment) most effective in early stage

Meniere

Page 14: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Intratympanic gentamycinProtocol

• Base line caloric before injection to determine degree of vestibular function in the other ear

• Standard protocol– 0.3-0.6 ml of gentamycin 40mg /ml (12-24 mg)– Repeated weekly till end points

• Low dose protocol– Single dose protocol– Injection of low concentration (10mg/ml)– Repeated after 2-4 weeks if vertigo remains

Meniere

Intratympanic injectionsEnd Point

• Hearing worsened– PTA increase > 15db

in 3 consecutive freq. – SDS fell > 20 %

• Nystagmus– Spontaneous paralytic– Head shaking– Head thrust

• 4 scheduled treatment

Head shaking

Head thrust

Meniere

Page 15: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Intractable vertigoProtocol

• Early stage: Mild / fluctuant hearing loss:– Intra-tympanic steroids if failed– Vestibular neurectomy

• Advanced stage: Moderate/ severe HL with poor discrimination:– Intra- tympanic gentamycin

Meniere

Management

• Vestibularsuppressant(3 days)

• Steroids

• Antiviral

• Vestibular Rehab.

Vestibular neuritis

Page 16: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Management

• Treatment of risk factors:– Hyperlipidemia; hypertension; diabetes;

smoking

• Drugs– Antiplatelet: Aspirin; plavix; persantin

• Neck care– Collars; Physiotherapy Cautions neck

movements

VBI

Management

• Trigger factors: avoidance• Drugs:

– Beta blockers: • Propanolol

– Calcium channel blockers:• Cinnarazine

– TCA antidepressant:• Amitryptiline (tryptizol)

– Novel antiepileptic: • Topamax

Migraine

Page 17: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Other conditions• Motion sickness • Orthostatic hypotension • Psychogenic Vertigo (hyperventilation)• Juvenile vertigo• Senile vertigo "presbyastasis" • Microvascular compression• Bilateral vestibular loss• Treatment of undetermined or ill defined

cause of vertigo

Management

• Prevention:– Anticholinergic (scopolamine) pure anticholinergics

are ineffective if administered after symptoms have already appeared

• Treatment:– Calcium channel blockers: Cinnarizine– Antihistamine: Dramamine

Motion Sickness

Page 18: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Nonpharmacologic treatment

• Slow, careful changes in position, especially on arising in the morning

• Avoidance of hot environments and hot showers or baths

• Multiple small meals

• Increased salt ;fluid and caffeine intake

Orthostatic Hypotension

Pharmacologic treatment

• Removal of medications that exacerbate hypotension when possible

• Fludrocortisone (Florinef)

• Midodrine (ProAmatine)

• Sympathomimetics

• Erythropoietin

Orthostatic Hypotension

Page 19: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Management

• Drugs:– Benzodiazepines– SSRI (selective serotonin reuptake inhibitors eg

cipralex ) less effectiveness but less habituation

• Breath into a bag in the event of an attack

• Psychiatric consultation is suggested.

Psychogenic vertigo

Management

• Antiepiletics– low dose– where the frequency

of the attacks is more than once a week..

BPV of childhood

Page 20: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Management

• Anti-convulsants:– Carbamazepine (Tegretol)– Gabapentin (Neuronton)

Microvascular compression

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Page 21: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity

Thank you

Page 22: Vertigo - Alexorlalexorl.edu.eg/alexorlfiles/pptorl2007/156003.pdf · Serotenergic pathway. Rheology RBC … Poor tissue Perfusion & oxygenation Inner ear vessel Poor vestibular activity