About prochlorperazinefirst-generation antipsychotic, phenothiazine derivative, antiemetic, antipsychotic,anxiolytic.mechanism of action of prochlorperazineantipsychotic action: prochlorperazine binds to the dopamine receptor (d1, d2, d3 &d4).it exerts its antipsychotic activity by blocking the dopamine projections in the limbic system and in mesocortical area. peripherally and centrally it acts as a competitive dopamine antagonist. prochlorperazine also produces alpha adrenergic blocking activity and anticholinergic activity. it also produces weak h1 antihistaminic activity and anti serotonin activity. antiemetic action: antiemetic activity is by blocking dopamine receptor (d2 receptor) in the chemoreceptor trigger zone (ctz) migraine: prochlorperazine has been used in migraine to control severe nausea and vomiting unresponsive to antiemetics and to relieve the pain of severe migraine attacks unresponsive to parenteral dihydroergotamine or sumatriptan.