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Typical antipsychotics (sometimes referred to as first generation antipsychotics, conventional antipsychotics, classical neuroleptics, traditional antipsychotics, or major tranquilizers) are a class of antipsychotic drugs first developed in the 1950s and used to treat psychosis (in particular, schizophrenia). Typical antipsychotics may also be used for the treatment of acute mania, agitation, and other conditions. The first typical antipsychotics to enter clinical use were the phenothiazines. Second-generation antipsychotics are known as atypical antipsychotics. Both generations of medication tend to block receptors in the brain's dopamine pathways, but atypicals at the time of marketing were claimed to differ from typical antipsychotics in that they are less likely to cause extrapyramidal motor control disabilities in patients, which include unsteady Parkinson's disease-type movements, body rigidity and involuntary tremors. More recent research has demonstrated the side effect profile of these drugs is similar to older drugs, causing the leading medical journal ''The Lancet'' to write in its editorial "the time has come to abandon the terms first-generation and second-generation antipsychotics, as they do not merit this distinction." These abnormal body movements can become permanent even after medication is stopped. == Adverse effects == Side effects vary among the various agents in this class of medications, but common side effects include: dry mouth, muscle stiffness, muscle cramping, tremors, EPS and weight gain. EPS refers to a cluster of symptoms consisting of akathisia, parkinsonism, and dystonia. Anticholinergics such as benztropine and diphenhydramine are commonly prescribed to treat the EPS. 4% of patients develop the Rabbit syndrome while on typical antipsychotics. There is a significant risk of the serious condition tardive dyskinesia developing as a side effect of typical antipsychotics. The risk of developing tardive dyskinesia after chronic typical antipsychotic usage varies on several factors, such as age and gender. The commonly reported incidence of TD among younger patients is about 5% per year. Among older patients incidence rates as high as 20% per year have been reported. The average prevalence is approximately 30%. There are no treatments that have consistently been shown to be effective for the treatment of tardive dyskinesias, however branched chain amino acids, melatonin, and vitamin E have been suggested as possible treatments. The atypical antipsychotic clozapine has also been suggested as an alternative antipsychotic for patients experiencing tardive dyskinesia. Tardive dyskinesia may reverse upon discontinuation of the offending agent or it may be irreversible. Neuroleptic malignant syndrome, or NMS, is a rare, but potentially fatal side effect of antipsychotic treatment. NMS is characterized by fever, muscle rigidity, autonomic dysfunction, and altered mental status. Treatment includes discontinuation of the offending agent and supportive care. The role of typical antipsychotics has come into question recently as studies have suggested that typical antipsychotics may increase the risk of death in elderly patients. A retrospective cohort study from the ''New England Journal of Medicine'' on Dec. 1, 2005 showed an increase in risk of death with the use of typical antipsychotics that was on par with the increase shown with atypical antipsychotics. This has led some to question the common use of antipsychotics for the treatment of agitation in the elderly, particularly with the availability of alternatives such as mood stabilizing and antiepileptic drugs. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Typical antipsychotic」の詳細全文を読む スポンサード リンク
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