Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In squirrel monkeys that had undergone repeated treatment with haloperidol at intervals of 7--14 days, subsequent acute administration of haloperidol induced dystonia and dyskinesias. This acute effect of haloperidol was dose-related and occurred at the same doses that impaired Sidman avoidance performance. Chlorpromazine, fluphenazine, metoclopramide, tetrabenazine, and Su-23397, all of which have been associated with extrapyramidal side effects, reliably elicited dyskinesias in these monkeys. Dyskinesias were less mared after thioridazine and absent after clozapine, corresponding to the reported lower incidence of extrapyramidal side effects in the clinic. The non-neuroleptics, baclofen, and diazepam, failed to elicit dyskinesias. In contrast to the dyskinetic syndrome, the incidence of catalepsy or tremor did not accurately predict propensity to elicit extrapyramidal symptomatology. The acute dyskinetic syndrome in squirrel monkeys may therefore serve as an animal model for predicting the ability of antipsychotics to cause extrapyramidal dysfunction, and may yield insight into the mechanisms of these drug-induced motor disorders.
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PMID:Neuroleptic-induced acute dyskinesias in squirrel monkeys: correlation with propensity to cause extrapyramidal side effects. 610 37

Most classifications of movement disorders emphasize their differential diagnosis and epidemiology according to clinical history and neurological examination. This review of movement disorders is organized according to the hypothesis of basal ganglia neurotransmitter imbalance in order to emphasize current research based on the pharmacology of these disorders. Specifically, dopamine (DA) excess and acetylcholine (ACh) deficiency may characterize part of the pathology of several hyperkinetic movement disorders including tardive dyskinesia, Huntington disease, Gilles de la Tourette syndrome, l-dopa dyskinesias, tardive Tourette syndrome, and toxic Tourette syndrome. The mirror image of this paradigm, namely DA deficiency and ACh excess, may characterize several rigid-dystonic movement disorders including Parkinson disease, drug-induced dystonias, and dystonia musculorum deformans. Finally, the unique combination of DA excess with ACh excess may characterize idiopathic orofacial dyskinesia (also known as Meige dystonia, Brueghel syndrome, and blepharospasm-oromandibular dystonia). Evidence supporting this formulation of movement disorders is reviewed, the limitations of this hypothesis are discussed, and new data from our own studies are presented.
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PMID:The neuropharmacology of tardive dyskinesia, spontaneous dyskinesia, and other dystonias. 612 51

Five Cebus apella monkeys with persistent neuroleptic-induced dyskinesia were given a single dose of sulpiride (20 mg/kg i.m.). The dyskinesia was reduced in all five although four developed attacks of acute dystonia which had to be reversed by anticholinergic medication in three animals. In one monkey the administration of classic neuroleptics had earlier been shown to induce a typical sequence of events. First there was a similar reduction of dyskinesia as seen in the other monkeys, 1-2 days later there was noticed a rebound deterioration lasting for several days. Metoclopramide 0.5 mg/kg, caused such a rebound effect (for 2 days), whereas sulpiride did not.
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PMID:Effects of sulpiride on persistent neuroleptic-induced dyskinesia in monkeys. 614 86

The clinical pharmacological, and neuroradiological observations in six patients with spontaneous blepharospasm-oromandibular dystonia (Meige's) syndrome are recorded. This group consisted of five males and one female, mean age at onset being 50.3 years. The duration of symptoms ranged from three months to 12 years, three patients having had symptoms for over four years. The dyskinesia was arrhythmic and asymmetrical in the orbicularis oculi and masseter muscles electrophysiologically. Pharmacological studies evinced no consistent response to parenteral physostigmine, no response to oral levodopa and no significant improvement in the dyskinesia following oral haloperidol. Lumbar air encephalogram was done in five patients, and showed frontal cortical atrophy without ventricular dilation in three. It is concluded that Meige's syndrome is a distinct nosological entity, and that physostigmine test is unlikely to be helpful in the differential diagnosis from neuroleptic-induced tardive dyskinesia. Neurotransmitter imbalance in the basal ganglia in this disorder remains to be established, and at present there is no satisfactory drug treatment for this progressively disabling movement disorder.
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PMID:Meige's syndrome: clinical, pharmacological and radiological observations. 627 56

Twenty-nine patients with tardive dyskinesia (n = 20) or related syndromes [spontaneous dyskinesia (n = 3), levodopa-induced dyskinesia (n = 3), tardive dystonia (n = 3)] were treated with clonidine. Clinical effects of this drug were observed for up to 4 years. Seventy-five percent of patients showed at least moderate improvement, and in 50% of patients, full resolution occurred. In most cases, patients received concomitant medications, including neuroleptics and benzodiazepines. Two patients received clonidine alone, and dyskinesia was only minimally improved; however, when bromocriptine was added, prompt improvement occurred on this combined regimen. On the basis of these findings, we suggest that not only receptor supersensitivity of dopaminergic neurons but also involvement of noradrenergic neurons is important in the pathophysiology of tardive dyskinesia and related syndromes.
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PMID:Clonidine therapy for tardive dyskinesia and related syndromes. 648 98

Four cases of dystonia occurring in two families are reported. The first symptoms consisting of dystonia and rigidity appeared early in childhood, in the first months in one family and of ages two and five years respectively in the other. In two cases, transient tremor was noted. These four children have been treated with L-dopa with prompt spectacular results, in cases 1 and 2, with more gradual less complete results in the others. L-dopa treatment was continued twelve, eleven, six, and five years, respectively, without any developmental problems. Motor function remains satisfactory and school work is normal. The only secondary effect observed was the occurrence of dyskinesia. The relation between L-dopa responsive dystonia and Parkinson's disease is discussed.
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PMID:Dystonia--L-dopa responsive or juvenile parkinsonism? 658 12

The long term consequences of the use of a dopamine agonist, bromocriptine, in the treatment of Parkinson's disease are reported. In a first study in 82 patients showing late side effects of levodopa, bromocriptine permitted a significant decrease of the gastro-intestinal adverse effects. In contrast, no significant improvement of end of dose deterioration from levodopa was noted. In cases where levodopa had ceased to be active, bromocriptine produced an improvement in the clinical state. The drug was ineffective in the very advanced stages of the disease or in the cases of dyskinesias without "on-off" effects. Bromocriptine did not significantly improve freezing or "on-off" effects, but reduced other side effects of levodopa, in particular dystonia. In a second group of 29 patients who had never received levodopa treatment, bromocriptine was shown to be very effective as a first treatment of the disease. The most important finding was the absence of long term side effects similar to those usually observed under levodopa: in this group and in comparison with 38 patients taking levodopa, dyskinesia, dystonia, oscillations in performance and especially "on-off" effects were not noted. However, a partial loss of efficacy of bromocriptine was observed in 27% of cases. In a third group of 10 patients, bromocriptine introduced according to a low and slow protocol was found to be active in limited number of patients only.
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PMID:Should dopamine agonists be given early or late in the treatment of Parkinson's disease? 671 21

Persistent signs of oral dyskinesia (tongue protrusion and facial grimacing) had developed as a result of earlier chronic treatment with neuroleptics in a Cebus apella monkey. When this animal was given single doses of any classical neuroleptic, a transient deterioration of dyskinesia occurred, preceded by a temporary abolishment of dyskinesia sometimes with an attack of acute dystonia. Fluphenazine (5-25 micrograms/kg) causes dose-related deteriorations of dyskinesia. Six different drugs were tested on this monkey for their capacity to elicit aggravation of dyskinetic signs: three antihistamines (brompheniramine, promethazine, diphenhydramine) and three dopamine D2 receptor antagonists (sulpiride, tiapride, metoclopramide). High doses of promethazine and diphenhydramine (5 mg/kg) induced a temporary alleviation of dyskinesia, possibly through sedation. All three D2 receptor antagonists precipitated signs of acute dystonia at some dose levels, but out of the test drugs only metoclopramide caused deterioration of dyskinetic symptoms. According to the present results only metoclopramide stands out as a drug with an inherent propensity to cause tardive dyskinesia.
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PMID:Application of a primate model for tardive dyskinesia. 684 25

The evaluation, diagnosis, and treatment of involuntary hyperkinetic movements can be a difficult challenge. A thorough history, including past and present drug use, and a complete physical, neurological, and psychiatric examination, accompanied by appropriate laboratory tests, are often necessary to make the correct differential diagnosis of dyskinesias. Movement disorders in psychiatric patients are usually related to neuroleptic medicines. Extrapyramidal syndromes related to starting these drugs include dystonia, akathisia, and parkinsonism, whereas dyskinesia occurs late in the course of the treatment. Involuntary movements may, however, be idiopathic, be caused by many other drugs, or occur as part of psychoses, hereditary neurodegenerative diseases, or other medical illnesses.
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PMID:The differential diagnosis of tardive dyskinesia. 694 30

We have treated 102 Parkinson patients with bromocriptine for up to 6 years; most of these posed problems of management when referred to us. Forty-two continue to take bromocriptine, at a mean dose of 49 mg daily (range 10-160), in combination with some 50% of their previous optimal dose of levodopa (with or without a decarboxylase inhibitor). We consider the main indications for bromocriptine are severe dyskinesia, early morning dystonia, and "wearing off" reactions. Contraindications include hallucinations, delusions, substantial confusion, acute myocardial infarction, active peptic ulceration, and active pleuropulmonary disease.
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PMID:Recent advances in the treatment of Parkinson's disease: the role of bromocriptine. 702 69


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