IS THE 5-HYDROXYTRYPTAMINE (5-HT) NEUROTRANSMITTER SYSTEM INVOLVED INREGULATION OF EXTRAPYRAMIDAL SYMPTOMS

Extrapyramidal symptoms (EPS) are thought to result from dopamine (DA) receptor blockade, but the serotonin (5-hydroxytryptamine; 5-HT) neur otransmitter system may also be involved. A Medline literature search was carried out followed by a cross reference search for those article s suggesting an interaction between dopaminergic and serotoninergic ne urotransmitter systems and EPS. This review suggests that 'atypical' a ntipsychotic drugs with 5-HT antagonistic properties possess higher th erapeutic efficacy together with reduced liability to induce EPS than typical antipsychotics. 5-HT reuptake inhibitors have also been report ed to produce EPS and the evidence from pre-clinical and clinical stud ies are suggestive of an interaction between 5-HT and DA neurotransmit ter systems. The result of this literature review suggests that it is possible that the 5-HT neurotransmitter system may regulate EPS by inf luencing the DA neurotransmitter system.