Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.1.8 (cholinesterase)
 12,691 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A middle aged man who inhaled sarin in a train in a subway station in Tokyo in 1995 and showed a variety of symptoms including psychiatric symptoms was reported. He experienced muscle weakness, dyspnea and unconsciousness of sudden onset immediately after exposure to sarin. Marked miosis was observed on admission. Plasma cholinesterase activity was remarkably decreased at that time. He also experienced delirium consisting of visual hallucination, insomnia and irritability at mid-night for more than seven days. These psychiatric symptoms gradually improved without any medication. To date there is no detailed description of such psychiatric symptoms in sarin poisoning.
 ...
PMID:[Psychiatric symptoms following accidental exposure to sarin--a case report]. 852 73

Visual hallucinations (VHs) are common psychiatric symptoms in patients with long-standing Parkinson's disease (PD). Treatment with neuroleptics or withdrawal of anti-PD drugs may improve VHs but will worsen motor dysfunctions. The authors report on 3 patients with long-standing PD who were treated with the cholinesterase inhibitor donepezil for the treatment of VHs. Each received a daily dose of 5 mg of donepezil, after reducing or discontinuing anti-PD medications had failed to relieve the VHs. In 2 patients (patient 1, 2), donepezil decreased VHs without worsening motor dysfunctions. In addition, the cognitive status of patient 2 improved. In patient 3, donepezil also resolved VHs, but delusions developed during treatment. After discontinuing donepezil, delusions disappeared and VHs reappeared. Donepezil may ameliorate visual hallucinations in PD patients, but controlled, double-blind trials are necessary to further clarify the effect of this drug on VHs in PD.
 ...
PMID:The beneficial effect of donepezil on visual hallucinations in three patients with Parkinson's disease. 1296 63

Neurologists and ophthalmologists should be familiar with the causes and treatment of visual hallucinations so that they are able to reassure patients and minimize the anguish associated with untreated visual hallucinations. Hallucinations are under-reported by patients because of the perceived psychiatric implication or because of poor insight into the unreal nature of the hallucinations. In the appropriate setting, physicians should specifically inquire about hallucinations as well as initiate medical treatment. Visual hallucinations have many etiologies and are associated with a variety of disorders. Identification of the associated disorder or cause is necessary to determine the appropriate treatment. Causes and associated disorders include ocular phenomena, migraine, seizures, visual loss (ie, release hallucinations), neurodegenerative disorders, midbrain injury, alcohol and drug effects, narcolepsy, post-traumatic stress disorder, and psychosis. Therapeutic treatment should be directed at the associated disorder or etiology. For instance, antiepileptic drugs may be appropriate for patients with irritative phenomena such as seizures and visual aura of migraine. Depending on the cause, other agents are available and include neuroleptics, cholinesterase inhibitors, and acetazolamide. Well-designed, randomized, controlled clinical trials regarding treatment of visual hallucinations associated with various disorders are lacking. Although complete resolution of visual hallucinations can be difficult, even minimal improvement may be symptomatically beneficial.
 ...
PMID:Visual Hallucinations. 1466 72

The neuropsychiatry of Parkinson's disease (PD) and its correlates are reviewed. Dementia occurs in up to 30% and can be treated with cholinesterase inhibitors. Cognitive impairments involve executive, visuospatial, attentional, and memory dysfunctions. Apathy may respond to dopamine agonists or cholines-terase inhibitors. Cognitive impairment, psychosis, and depression predict quality of life. Visual hallucinations and paranoia are common, and respond to low dose clozapine. Depression is common and predicts caregiver burden and depression. The best data suggest the efficacy of nortriptyline and the safety of SSRIs. Anxiety disorders occur in 40% of patients, especially off-period panic attacks and specific phobias. Bromazepam has proven useful for anxiety in PD, but buspirone has only diminished drug-induced dyskinesias to date. Sleep disorders occur in up to 94% of patients. Insomnia is common and is treated by dopaminergic agent dose reduction, nocturnal dosing, treatment of depression, or use of short half-lived hypnotics, depending on etiology. Parasomnias include REM behavior disorder and vivid dreams and nightmares. Excessive daytime somnolence occurs in at least 15% of patients. Sleep attacks are common and patients should be warned about driving when taking dopamine agonists. Sexual disorders occur in most patients. Paraphilias are associated with dopamine agonists, and clozapine may be useful in their treatment. Surgical therapies are associated with a wide variety of neuropsychiatric features, and vigilance for suicide attempts with subthalamic nucleus stimulation seems warranted. Neuropsychiatric disorders are important determinants of quality of life and caregiver burden in PD. More clinical research is needed to establish effective treatments.
 ...
PMID:The neuropsychiatry of Parkinson's disease. 1617 59

We aimed to determine prospectively whether rivastigmine, an inhibitor of acetylcholinesterase and butyrylcholinesterase, provided benefits in patients with and without visual hallucinations in a population with dementia associated with Parkinson's disease (PDD). This was a 24-week double-blind placebo-controlled study. Primary efficacy measures were the Alzheimer's Disease Assessment Scale cognitive subscale (ADAS-cog) and Alzheimer's Disease Cooperative Study-Clinician's Global Impression of Change (ADCS-CGIC). Secondary efficacy measures included activities of daily living, behavioral symptoms, and executive and attentional functions. Patients were stratified according to the presence of visual hallucinations at baseline. The study included 188 visual hallucinators (118 on rivastigmine, 70 on placebo) and 348 nonvisual hallucinators (239 on rivastigmine, 109 on placebo). Rivastigmine provided benefits in both visual hallucinators and nonvisual hallucinators. Absolute responses to rivastigmine on the ADAS-cog were comparable over 6 months, although rivastigmine-placebo differences tended to be larger in visual hallucinators (4.27; P = 0.002) than in nonhallucinators (2.09; P = 0.015). On the ADCS-CGIC, differences between rivastigmine and placebo were 0.5 in visual hallucinators (P = 0.030) and 0.3 in nonhallucinators (P = 0.111). Rivastigmine provided benefits on all secondary efficacy measures, and placebo declines and treatment differences were more marked in visual hallucinators. Adverse events were reported more frequently by rivastigmine-treated patients, although this difference was less marked in visual hallucinators. Visual hallucinations appear to predict more rapid decline and possibly greater therapeutic benefit from rivastigmine treatment in PDD.
 ...
PMID:Effects of rivastigmine in patients with and without visual hallucinations in dementia associated with Parkinson's disease. 1737 57

I report here clinical effects of cholinesterase inhibitors (rivastigmine and donepezil) on visual hallucinations emerging in the course of Parkinson's disease (PD) and clinically unresponsive to antipsychotics. Five patients with PD (with or without dementia) complicated by visual hallucinations and unresponsive to atypical antipsychotics were offered a 12-week, open-label trial of a cholinesterase inhibitor. All 5 subjects completed the trial with no major adverse effects and, of note, no discontinuations due to adverse events. Visual hallucinations resolved in 4 subjects and were markedly diminished in one person. Neither changes in UPDRS scores nor exaggeration of subjective complaints about extrapyramidal symptoms were noted during treatment. Cholinesterase inhibitors might represent a useful alternative to antipsychotics for patients with PD accompanied by visual hallucinations even in the absence of dementia. One must, however, not forget that their use with this indication remains experimental and safety measures as well as accurate clinical surveillance are of crucial importance.
 ...
PMID:Parkinson's disease-related visual hallucinations unresponsive to atypical antipsychotics treated with cholinesterase inhibitors: a case series. 1762 23

The authors review current literature on hallucinations in Parkinson's disease (PD). Recent neuropathological studies showed that hallucinations occur in synucleinopathies and are a significant predictor of Lewy Body depositions. Therefore, hallucinations are a hallmark of PD and of dementia with Lewy Bodies. Visual hallucinations are mostly complex and kinematic; preserved or disturbed insight on the nature of hallucinations is a major prognostic factor, although eventually all hallucinators will present with reduced insight. Current theories on the origin of hallucinations point to visual dysfunction, dream overflow and cognitive impairment, yet objection can be raised on each one of the putative models of hallucinations. Understanding of the origin of hallucinations is required in order to develop treatments: all treatment evaluations were focused in general on psychosis, and only clozapine obtained positive evidence-based ratings on efficacy. However, it is likely that cholinesterase inhibitors, antipsychotics and anti-5-hydroxytryptamine(3) agents and drugs acting on sleep regulation will have different and perhaps opposite effects on different types of hallucinations, whether they are accompanied by disturbed insight, sleep disorders or other psychotic features. Further studies will try to separate phenomenology and responses to treatment and will investigate the relevance of concomitant sleep disorders and abnormality of frontoparietal networks involved in the attention process.
 ...
PMID:New approaches to understanding hallucinations in Parkinson's disease: phenomenology and possible origins. 1805 66

Visual hallucinations are a typical feature of Lewy body parkinsonism and occur in some 40% of patients with Parkinson's disease. Age and cognitive decline are the most important intrinsic risk factors, but hallucinosis is often triggered by comorbid conditions such as infection and dehydration. The single most important trigger, however, is exposure to CNS drugs, in particular antiparkinsonian agents. While hallucinosis and psychosis can be triggered by amantadine and anticholinergics, they are more commonly experienced after changes in dopaminergic medication. Dopamine agonists have greater potential to induce hallucinosis compared with L-dopa. Attempting to reduce antiparkinsonian drugs is an important part in the management of these patients, but atypical neuroleptics like clozapine or quetiapine are frequently necessary. Visual hallucinations in Parkinson's disease patients with dementia can also be improved by treatment with the cholinesterase inhibitor rivastigmine.
 ...
PMID:When a Parkinson's disease patient starts to hallucinate. 1864 10

Visual hallucinations (VHs) represent a frequent and disturbing complication of Parkinson's disease. Evidence suggests that VH can be related to central cholinergic dysfunction. Short-latency afferent inhibition (SAI) technique gives the opportunity to test an inhibitory cholinergic circuit in the human cerebral motor cortex. This inhibition of motor-evoked potentials can be observed when transcranial magnetic stimulation is delivered with a delay ranging from 2 to 8 ms, after a peripheral nerve afferent input has reached the somatosensory cortex. We applied SAI technique in 10 non-demented patients with Parkinson's disease with VHs, in 12 non-demented patients with Parkinson's disease without VHs (NVH-pts) and in 11 age-matched normal controls. All patients with Parkinson's disease underwent a battery of neuropsychological tests to assess frontal and visuospatial functions, memory and attention. SAI was significantly reduced in patients with VHs compared with controls and patients without VHs. Neuropsychological examination showed a mild cognitive impairment in 16 out of 22 patients with Parkinson's disease. In addition, we found that in our patients with VHs, performance of some tasks evaluating visuospatial functions and attentional/frontal lobe functions was significantly more impaired than in patients without VHs. SAI abnormalities, presence of VH and neuropsychological results strongly support the hypothesis of cholinergic dysfunction in some patients with Parkinson's disease, who will probably develop a dementia. A follow-up study of our patients is required to verify whether SAI abnormalities can predict a future severe cognitive decline. Moreover, SAI can also be very useful to follow-up the efficacy of anti-cholinesterase therapies.
 ...
PMID:Functional involvement of central cholinergic circuits and visual hallucinations in Parkinson's disease. 1958 99

Psychotic symptoms are common in drug treated patients with Parkinson's disease (PD). Visual hallucinations occur in about 30% and delusions, typically paranoid in nature, occur in about 5%. These problems, particularly the delusions, cause great distress for patient and caregivers, and are among the most important precipitants for nursing home placement. Psychotic symptoms carry a poor prognosis. They often herald dementia, and are associated with increased mortality. These symptoms often abate with medication reductions, but this may not be tolerated due to worsened motor function. Only clozapine has level A evidence to support its use in PD patients with psychosis (PDP), whether demented or not. While quetiapine has been recommended by the American Academy of Neurology for "consideration," double blind placebo controlled trials have demonstrated safety but not efficacy. Other antipsychotic drugs have been reported to worsen motor function and data on the effectiveness of cholinesterase inhibitors is limited. PDP remains a serious problem with limited treatment options.
...
PMID:Parkinson disease psychosis: Update. 2324 58


1 2 Next >>