Menieres Disease Flashcards
1
Q
Meniere’s disease
Pathophysiology
A
- Meniere’s disease is an inner-ear condition that can cause vertigo, a specific type of dizziness in which you feel as though you’re spinning.
- It also can cause ringing in your ear (tinnitus), hearing loss that comes and goes, and a feeling of fullness or pressure in your ear. Usually, only one ear is affected. The hearing loss eventually can be permanent.
2
Q
Betahistine
Indications
A
- Vertigo, tinnitus and hearing loss associated with Meniere’s disease
3
Q
Betahistine
MOA- Histaminergic activity
A
- Betahistamine (Histamine)- Acts as a partial H1 agonist and H3-antagonist also in neuronal tissue (NB- No H2 activity)
- Betahistine increases histamine turnover and release by blocking pre-synaptic H3-receptors and inducing H3-receptor downregulation
- Betahistine may increase blood flow to the cochlear region as well as the whole brain
4
Q
Betahistine
MOA- Vestibular compensation
A
- Betahistine accelerates the vestibular recovery after unilateral neurectomy in animals, by promoting and facilitating central vestibular compensation
- This effect is characterised by up-regulation of histamine turnover and release it H3-antagonism
5
Q
Betahistine
MOA- Alters neuronal firing in the vestibular nuclei
A
- Betahistine has a dose-dependent inhibiting effect on spike generation of neurons in lateral and medial vestibular nuclei
- The efficacy of betahistine was shown in studies in patients with vestibular vertigo and with Meniere’s disease as was demonstrated by improvements in severity and frequency of vertigo attacks
6
Q
Betahistine
Warnings
A
- Contraindicated in
- Phaeochromocytoma- a rare, usually noncancerous tumor that develops in an adrenal gland
- Cautioned in
- Asthma
- History of peptic ulcer
7
Q
Betahistine
Adverse effects
A
- Nausea and Dyspepsia
- Headache
- Hypersensitivity
8
Q
Betahistine
Interactions
A
- Cautioned when using MOAI
- Antihistamines cancel the effects of betahistine
