ICD-10 Specific code R11: Nausea and vomiting

Chlorpromazine is a phenothiazine neuroleptic. Chlorpromazine has depressant actions on the Central Nervous System, with alpha-adrenergic blocking and anticholinergic activities. It has anti-emetic, anti-puritic, serotonin-blocking and weak anti-histamine properties and slight ganglion blocking activity.

Cyclizine is a histamine H₁ receptor antagonist of the piperazine class which is characterised by a low incidence of drowsiness. It possesses anticholinergic and antiemetic properties. The exact mechanism by which cyclizine can prevent or suppress both nausea and vomiting from various causes is unknown.

Dimenhydrinate is a theoclate salt of the ethanolamine derivative diphenhydramine. It exhibits reversible competitive antagonism with histamine for the capture of H1 receptors. It has anticholinergic (antimuscarinic) properties that explain the anti-emetic action of the drug in cases of labyrinthial irritation (nausea, vertigo), and the central suppression it causes.

Domperidone is a dopamine antagonist with anti-emetic properties, Domperidone does not readily cross the blood-brain barrier. In domperidone users, especially in adults, extrapyramidal side effects are very rare, but domperidone promotes the release of prolactin from the pituitary.

Perphenazine is a depressant which blocks dopamine receptors in the central nervous system. It binds to dopamine D₁ and D₂ receptors and inhibits their activity. Its antiemetic action is mainly due to the inhibition of D₂ receptors in the center of the vomiting. Perphenazine also binds to alpha adrenergic receptors and in conjunction with G proteins activate the phosphatidylinositol-calcium system.

Trifluoperazine is one of the phenothiazine class of compounds and as such has many pharmacodynamic effects which relate to its therapeutic actions and side effects. The most notable action of phenothiazines is antagonism at dopamine receptors in the CNS.