Pharmacology

Question 1

What are the causes of nausea and vomiting

Answer 1

Ingestion of irritants, bac, toxins
Distention of stomach
Motion sickness 
Pharyngeal reflex 
Stress
Opioid 
Cytotoxic drug
Post operative

Question 2

What are the stimuli for emetic centre

Answer 2

1. Cerebral cortex (pain, smell, emotions)
2. Vestibular system (motion and balance, miss match)
3. chemoreceptor trigger zone CTZ (blood, nerve)
4. Peripheral centre (GIT via afferent fibres)

Question 3

Where can emetic centre be found

Answer 3

Medulla oblongata

Question 4

Describe the activation pathway of emetic response by peripheral stimuli

Answer 4

Ingestion of irritants etc. / cytotoxic drug causing damage in GIT
Entrochromaffin cells ( endocrine) release serotonin 5HT onto VAGAL AFFERENT SENSORY NERVE
Stimulation of 5HT3 rec
Depolarisation
Send signal to higher centres
Activation of ab muscles, diaphragm and esophsgus

Question 5

What are the neurotransmitter receptors found in CTZ?

Answer 5

5-HT R3 serotonin 
Histamine H1
Dopamine D2
Neuropeptide 
Miu-delta opioid

Question 6

Where can CTZ be found

Answer 6

In medulla oblongata