Antipsychotics dystonia

Among the most significant adverse reactions associated with the antipsychotic dm are the extrapyramidal effects. The term extrapyramidal effects refers to a group of adverse reactions occurring on the extrapyramidal portion of the nervous system as a result of antipsychotic drains. This part of the nervous system affects body posture and promotes smooth and uninterrupted movement of various muscle groups. Antipsychotics disturb the function of the extrapyramidal portion of the nervous system, causing abnormal muscle movement. Extrapyramidal effects include Parkinson-like symptoms (see Chap. 29), akathisia, and dystonia (see Display 32-1). 

Extrapyramidal symptoms (EPS) Adverse effects of medications such as antipsychotics. EPS include dystonia (involuntary muscle contractions), tardive dyskinesia (repetitive, involuntary movements), parkinsonian symptoms (akinesia and tremors), and akathisia (motor restlessness or anxiety). 

The answer is c. (Hardman, pp 414-4163) Unwanted pharmacologic side effects produced by phenothiazine antipsychotic drugs (e.g., perphenazine) include Parkinson-like syndrome, akathisia, dystonias, galactorrhea, amenorrhea, and infertility. These side effects are due to the ability of these agents to block dopamine receptors. The phenothiazines also block muscarinic and a-adrenergic receptors, which are responsible for other effects. 

Two extrapyramidal conditions, acute dystonia and akathisia, occur early during treatment, while parkinsonism tends to evolve gradually over days to weeks. All three reactions occur most commonly with the high-potency antipsychotics (Table 34.1) and are related to high Dz-receptor occupancy. Acute dystonia, which occurs in about 5% of patients on antipsychotic therapy, consists of uncontrollable movements and distortions of the face, head, and neck. It can be treated with centrally acting an-timuscarinic agents, such as benztropine, while antipsychotic therapy is temporarily discontinued. When this reaction subsides, the anticholinergic can be withdrawn. 

The working assumption that the striatal system is only involved with extrapyramidal function (e.g., parkinsonian side effects, dystonias, and TD) and that the mesolimbic or mesocortical systems are only involved with psychosis may be an oversimplification. Many of the neuroanatomical studies on the identified dopaminergic tracts are done with rats. In the monkey, by contrast, there are many more DA tracts that are either absent in the rat or at least markedly different human systems could be different from the rat s or monkey s. Understanding the neuropharmacology of the antipsychotics is further complicated, given that neither the mesolimbic-mesocortical nor the striatal systems are homogeneous but may also include various subsystems. 

Lorazepam (2 mg i.m.) was found to be equivalent to haloperidol (5 mg i.m.) either alone or when added to ongoing antipsychotic treatment, and significantly reduced the likelihood of akathisia and dystonia (167). In the treatment of acute mania, lorazepam has also been reported useful as an adjunct to lithium, as well as antipsychotics (157, 163, 165, 168, 169). 

Antipsychotics are a chemically diverse group of drugs having in common the ability to ameliorate psychotic symptoms. Unfortunately, a significant percentage of patients fail to respond adequately or may develop adverse effects such as acute EPS, various tardive syndromes (e.g., TD, dystonia, etc.), and, less commonly, even more serious adverse events such as NMS and agranulocytosis. 

As in adults, the main acute untoward effects of high-potency, typical antipsychotics are extrapyramidal symptoms (EPS) syndromes, particularly acute dystonia, and sedation (167). Parkinsonism is rare in preschool-aged children but does occur in school-aged children and adolescents. 

Prochlorperazine Maleate. 2-Chloro-10-[3-(4-methyl-l-piperazinyl)-propyl]-10 H-phenothiazine maleate [84-02-6] (Compazine) (22) is a white or pale yellow crystalline powder. It is almost completely odorless, its saturated solution is acidic to litmus, it is practically insoluble in water and ethanol, and it is slightly soluble in warm chloroform. It may be made by the synthesis described in Reference 18. Prochlorperazine maleate [84-02-6] is an effective antiemetic and tranquilizing agent. It is not particularly effective for motion sickness. Adverse reactions that may occur include extrapyramidal reactions, motor resdessness, dystonias, tardive dyskinesia, and contact dermatitis. Prochlorperazine is also a significant phenothiazine antipsychotic. 

Unfortunately, these drugs—especially the first generation of antipsychotics introduced in the 1950s—have side effects similar to those seen in patients with Parkinson s disease tremors when at rest, reduction of voluntary movement, muscle spasticity and dystonia, or sustained muscle contractions. These symptoms confirm the role of dopamine neurons in the initiation and control of movement. Antipsychotic drugs also block dopamine receptors within a region of the brain that controls... 

Regarding neuroleptic-induced dystonias, it is well known that typical neuroleptics cause catalepsy in rats and movement disorders in man. By contrast, the atypical neuroleptics clozapine and sulpiride have a low propensity to cause movement disorders in man even though they have established antipsychotic effects. These atypical neuroleptics, unlike many of the typical neuroleptics, have a low affinity for sigma receptors which lends support to the hypothesis that the dystonias produced by typical... 

Burke, R., Fahn, S., Jankovic, J., Marsden, C. D., Lang, A. E., Gollomp, S., et al. (1982). Tardive dystonia Late-onset and persistent dystonia caused by antipsychotic drugs. 

Acute dystonia is a recognized complication of treatment with antipsychotic drugs and it can also occur with SSRIs and the anxiolytic drug buspirone. 

Christodoulou C, Kalaitzi C. Antipsychotic drug-induced acute laryngeal dystonia two case reports and a mini review. J Psychopharmacol 2005 19 307-12. 

Burke RE, Fahn S, Jankovic J, Marsden CD, Lang AE, Gollomp S, Ilson J. Tardive dystonia late-onset and persistent dystonia caused by antipsychotic drugs. Neurology 1982 32(12) 1335-46. 

Raja M. Managing antipsychotic-induced acute and tardive dystonia. Drug Saf 1998 19(l) 57-72. 

Patients taking olanzapine reported a low incidence of dystonias, which may be about 0.3% (SEDA-22, 56). In the light of two new cases of acute dystonia associated with olanzapine in patients with previous history of dystonia or parkinsonism related to antipsychotic treatment, comparative figures have been reported. Acute dystonia occurred in 1.4% of patients who took olanzapine, compared with 5.0-6.3% of those taking haloperidol (84). 

Two patients with schizophrenia who developed focal tardive dystonia with atypical antipsychotic drugs (risperidone and olanzapine) had marked sustained improvement when quetiapine was gradually introduced and the other antipsychotic drugs were withdrawn there was no loss of control of psychotic symptoms (10). 

Gourzis P, Polychronopoulos P, Papapetropoulos S, Assimakopoulos K, Argyriou AA, Beratis S. Quetiapine in the treatment of focal tardive dystonia induced by other atypical antipsychotics a report of 2 cases. Clin Neuropharmacol 2005 28 195-6. 

INDIRECT ANTIPSYCHOTICS 1. Case reports of paralytic ileus with trifluoperazine and methylphenidate 2. Case report of acute dystonias with haloperidol and dexamfetamine 3.1 efficacy of chlorpromazine when dexamfetamine was added 1. Additive anticholinergic effect 2. Uncertain possibly due to t dopamine release 3. Uncertain 1. Watch for signs of altered bowel habit 2. Warn patients of this rare interaction 3. Avoid co-administration... 

The primary treatment for schizophrenia involves use of antipsychotic medications. These are classified as typical or first generation, and atypical. The atypical antipsycho tics differ from the typical in having relatively less extrapyramidal side effects, such as rigidity, dystonia (muscle spasm), akathi-sia (motor restlessness), and pseudo-Parkinsonian symptoms. 

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