Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the effect of olanzapine (1 to 15 mg/d) in 15 nondemented parkinsonian patients with drug-induced psychosis. Psychotic symptoms decreased significantly during treatment, and there was no worsening of extrapyramidal symptoms. These results suggest that olanzapine is a well-tolerated and effective treatment for drug-induced psychosis in nondemented patients with Parkinson's disease.
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PMID:Olanzapine in the treatment of dopaminomimetic psychosis in patients with Parkinson's disease. 956 37

1. Previous experiments have suggested a potential atypical antipsychotic activity of the ergoline derivative LEK-8829. In vitro experiments showed a high affinity to 5-HT1A, 5-HT2 and D2 receptors (the ratio of pKi values 5-HT2/D2 = 1.11) and a moderate affinity to D1 receptors. In vivo experiments showed antagonism of dopamine and 5-hydroxytryptamine (5-HT) receptor-linked behaviours. 2. In the present study, the rats with unilateral dopaminergic deafferentation of the striatum, induced by the lesion of the median forebrain bundle with 6-hydroxydopamine (6-OHDA), were used to determine the effects of LEK-8829 on turning behaviour and on striatal c-fos mRNA levels. 3. The administration of LEK-8829 induced a long lasting contralateral turning behaviour that was dose-dependent. It was found that the specific D1 receptor antagonist SCH-23390 but not the D2 receptor antagonist haloperidol or 5-HT1A antagonist pindolol, dose-dependently inhibited the turning behaviour induced by LEK-8829. 4. In an attempt to clarify the D1:D2 receptor interactions involved in the action of LEK-8829 in the 6OHDA model, we used in situ hybridization histochemistry to compare the effect of SCH-23390 pretreatment on striatal c-fos mRNA expression induced either by LEK-8829 or by the typical antipsychotic haloperidol. 5. LEK-8829 induced a bilateral striatal c-fos mRNA expression that was significantly higher in the denervated striatum as compared to the intact striatum and was completely blocked on both sides by pretreatment with SCH-23390. In contrast, haloperidol-induced striatal c-fos mRNA expression was limited to the innervated striatum and was not blocked by SCH-23390. 6. Our data demonstrate an intrinsic activity of LEK-8829 on D1 receptors that is potentiated in the dopamine-depleted striatum. We conclude, therefore, that the putative atypical antipsychotic LEK-8829 may prove useful as an experimental tool for the study of D1:D2 receptor interactions and could have beneficial effects in the treatment of drug-induced psychosis in patients with Parkinson's disease.
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PMID:The D1 receptor-mediated effects of the ergoline derivative LEK-8829 in rats with unilateral 6-hydroxydopamine lesions. 893 22

Parkinson's disease (PD) is a progressive neurological condition that causes considerable disability in the elderly. Drugs used to treat PD, such as levodopa, offer symptomatic relief but often have neuropsychiatric adverse effects, most prominently psychosis and delirium. Aged patients and those with dementia are particularly vulnerable to these adverse effects. Evaluating PD patients with drug-induced neuropsychiatric adverse effects is made difficult by their complex clinical presentations. The treatment of drug-induced psychosis and delirium begins with manipulating the antiparkinsonian drug regimen, but this frequently worsens motor function. Atypical antipsychotics such as clozapine have been successfully employed to treat the psychosis without worsening the motor disability. Patient intolerance of clozapine therapy has prompted open-label studies with newer agents such as risperidone, remoxipride, zotepine, mianserin and ondansetron.
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PMID:Neuropsychiatric adverse effects of antiparkinsonian drugs. Characteristics, evaluation and treatment. 914 57

Levodopa-induced psychosis can complicate the treatment of Parkinson's disease (PD). In this retrospective, uncontrolled report, we describe our experience treating PD-related psychosis with clozapine, emphasizing those patients treated for longer than 1 year. Twenty-seven patients were treated, 14 for longer than 1 year. Most patients showed a rapid improvement from baseline within 1 month using the Clinical Global Impression and Global Psychosis Rating Scores. Five patients discontinued the drug due to side effects, but only two patients reported side effects after 6 months of treatment. Clozapine appears to be effective in treating PD related psychotic symptoms while not interfering with motor function.
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PMID:Use of clozapine to treat levodopa-induced psychosis in Parkinson's disease: retrospective review. 918 21

Clozapine, the only commercially available atypical neuroleptic, is approved for the treatment of schizophrenic patients who are unresponsive to or intolerant of typical neuroleptics. It has an unusual pharmacologic profile compared with standard neuroleptics, and it follows that clinical response to this drug is also different. It has shattered the notion that a drug must be capable of inducing or worsening parkinsonism to be a potent antipsychotic. Based on these findings, it is being used increasingly by neurologists for psychiatric and nonpsychiatric problems in patients with movement disorders. The most common use for clozapine among neurologists is in the management of drug-induced psychosis in Parkinson's disease (PD). This problem has been a source of increased morbidity and mortality in PD because of a lack of adequate therapeutic intervention. At this time, because of success in numerous open trials, with improvement of > 80% of patients, clozapine therapy for psychosis in PD is becoming the standard of care. It also appears to be of value in the management of some motor features of PD, including tremors and dyskinesia and possibly even sensory symptoms such as akathisia and pain. The literature also suggests that clozapine may be of potential benefit in hyperkinetic movement disorders including essential tremor, Huntington's disease, and tardive dyskinesia. We review the current data concerning the use of clozapine in patients with these movement disorders and others.
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PMID:The emerging role of clozapine in the treatment of movement disorders. 925 Oct 65

The Parkinson Psychosis Rating Scale (PPRS) was designed to assess the severity of specific symptoms of levodopa-induced psychosis in patients with Parkinson's disease. The scale is administered by the clinician and consists of six items, each rated from 1 (no symptoms) to 4 (extreme symptoms); total score ranges from 6-24 points. To test its reliability, validity, and stability, the authors administered the PPRS to 29 patients with parkinsonian psychosis before and after a 6-week course of treatment with the 5HT3 antagonist ondansetron. Each patient and their caregivers were interviewed by three raters. Results were compared with two other available psychotic symptom scales and one cognitive scale given to the same patients. It was found that the interrater reliability for the total PPRS scores and for each of the individual items was high (Spearman's rho = 0.80-0.99). A significant reduction in PPRS scores was obtained after ondansetron administration, concomitant with a decrease in the Global Functional Impairment score, which was assessed by the family. The changes in PPRS scores occurred irrespective of cognitive dysfunction, as measured by the Minimental State Examination. It appears that the PPRS is a relevant, reliable, valid, and easily-administered instrument for measuring the severity of parkinsonian psychosis. Further studies are needed to evaluate its utility in other organic psychoses and in the assessment of additional pharmacologic treatments for levodopa-induced psychosis.
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PMID:Parkinson Psychosis Rating Scale: a practical instrument for grading psychosis in Parkinson's disease. 978 7

Quetiapine is an atypical antipsychotic with clozapine-like pharmacology but without associated agranulocytosis. We report our complete experience with quetiapine for the treatment of drug-induced psychosis (DIP) in Parkinson's disease (PD). Thirty-five patients with PD and DIP aged 75 years (range, 58-89) with a mean PD duration of 8.4 years on an average of 427 mg levodopa per day received a mean dose of 40.6 mg quetiapine daily. Twenty of 24 neuroleptic-naive patients reported marked improvement of psychosis without a decline in motor function as assessed by the Unified Parkinson's Disease Rating Scale (UPDRS-motor). Ten patients had a baseline and 4-week follow-up assessment using the Mini-Mental Status Examination (MMSE) and Brief Psychiatric Rating Scale (BPRS). The improvement in BPRS score (32.6 versus 22.8) was clinically and statistically significant (p = 0.024). Three of 24 were unable to tolerate quetiapine because of orthostatic hypotension, headache, nausea, and persistence of hallucinations. One patient died of an unrelated cause. We also tried to switch 11 psychiatrically stable patients on clozapine (eight) and olanzapine (three). Five patients made this transition without a loss of effect as measured on BPRS and MMSE. Six did not (five on clozapine, one on olanzapine) because of confusion, erratic behavior, and increased hallucinations. No crossover failure had worsened PD except for increased tremor in one. Quetiapine is useful and well-tolerated as a first drug to treat DIP in PD but must be used cautiously to replace other atypical antipsychotic drugs.
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PMID:Quetiapine for the treatment of drug-induced psychosis in Parkinson's disease. 1034 74

The management of Parkinson's disease has undergone recent changes with the advent of new therapies, both pharmacotherapy and surgery. Available interventions are discussed. Levodopa remains the mainstay of therapy. New drugs include the dopamine agonists and COMT inhibitors. New dopamine agonists which may have a levodopa "sparing effect;" it has been suggested that some of the drugs should be considered as first line treatments for newly diagnosed Parkinson's disease patients. We review roles of these drugs. The concept of neuroprotection in neurodegenerative disorders such as Parkinson's disease became popular in the mid 1980s and it is hoped that eventually therapy will be directed at slowing progression of the disease. A great deal more work needs to be done before a suitable agent is identified as being neuroprotective. Potential neuroprotective agents are reviewed. Surgical therapies for Parkinson's disease consisting of various forms of lesion surgery as well as stimulation procedures are reviewed. Complications of drug therapy include motor problems such as motor response fluctuations, as well as psychiatric complications including levodopa-induced psychosis. Atypical neuroleptic agents and ECT for psychiatric syndromes associated with Parkinson's disease are discussed. Algorithms for the management of early disease as well as the management of psychosis in Parkinson's disease are included. Treatment options for advanced disease are tabulated.
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PMID:Management of Parkinson's disease a review of current and new therapies. 1097 42

Clozapine is the current treatment of choice for drug-induced psychosis (DIP) occurring in Parkinson's disease. However, alternative medications have been sought because of the small but significant risk of agranulocytosis and the need for frequent blood testing. The new "atypical" antipsychotic olanzapine (OLZ) has recently been proposed as a safe and effective option for treating psychosis in this setting. To investigate this, we retrospectively evaluated all 12 of our patients treated with OLZ for DIP. Symptoms of psychosis were improved in nine of 12 patients, but nine of 12 patients also experienced worsening of motor functioning while on OLZ. The worsening was considered dramatic in six of these patients. Overall, there was no significant increase in levodopa doses on OLZ. Only one patient remained on OLZ at the time of the analysis. Nine patients were switched to alternative treatment for DIP. We conclude that although OLZ may improve symptoms of psychosis in parkinsonian patients, it can also worsen motor functioning. In some patients, the degree of motor worsening may be intolerable.
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PMID:Worsening of motor features of parkinsonism with olanzapine. 1058 79

This paper gives an overview of the clinical importance of SPECT and PET imaging of the dopaminergic system in the differential diagnosis and for the determination of the progression rate of Parkinson's disease (PD). D2 receptor imaging can help to differentiate multiple system atrophy (MSA) and progressive supranuclear palsy (PSP) from PD. In patients treated with neuroleptics it is possible to determine the rate of striatal D2 receptor blockade using this technique. This occupancy rate parallels the occurrence of parkinsonian side effects. Its measurement helps in the selection of newer atypical neuroleptics, which can be used to treat drug-induced psychosis in PD because they do not aggravate parkinsonian symptoms. Imaging of dopaminergic neurons with [123I]beta-CIT SPECT or [18F]DOPA PET is a way to visualize and quantify the nigrostriatal dopaminergic lesion in PD. Findings correlate with clinical rating scales and demonstrate the feasibility of detecting the preclinical lesion in patients with hemiparkinson or familial PD. [123I]beta-CIT SPECT can easily distinguish patients with essential tremor and patients with "lower body parkinsonism" due to a subcortical vascular encephalopathy. MSA and PSP cannot be separated from PD with this method alone. Longitudinal studies with [123I]beta-CIT SPECT and [18F]DOPA PET can quantify the progression rate in PD. SPECT results from our own group show a low rate of progression in patients with a long duration of disease and a more marked progression rate in patients with shorter disease duration. In the former group regions in the striatum with higher beta-CIT binding at the time of the first SPECT scan decline faster than regions with lower binding. These findings suggest a curvilinear course of progression which starts at different time points in different striatal regions and which levels off after several years of disease duration. These findings are in line with data from PET studies and underline the importance of an early start of neuroprotective strategies. Preliminary data from PET and SPECT studies in early PD suggest that dopamine agonists might have a slight neuroprotective effect and might slow down the rate of progression of the disease.
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PMID:SPECT and PET imaging of the dopaminergic system in Parkinson's disease. 1119 11


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