Drugs used in nausea and vertigo antiemetics

1 Umbiv citrtex. These presumably account for the nausea associated with unpleasant odours and sights. Cortical afferents are also involved in the conditioned vomiting reflex that may occur when patients see or smell the cytotoxic drugs they are about to receive. 

3 Km-leiis Mlitarius. These complete the arc for the gag reflex (i.e. the reflex caused by poking a finger in the mouth). 

4 Spinal cord (spinoreticular fibres). These are involved in the nausea that accompanies physical injuiy. 

The transmitters involved in the pathways concerned with emesis are not fully known. However, the CTZ is rich in dopamine-D, and 3HT, receptors. Cholinergic and hisiaminergic synapses are involved in transmission from the vestibular apparatus to the vomiting centre. 

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