Chronic Neuroleptic Therapy Research Articles

25. The influence of neuroleptic treatment on the occurrence of epileptic status

Purpose: Proconvulsive and proepileptogenic effects of neuroleptics had been described a long ago. Based on the small number of studies it is estimated that patients treated with optimal therapeutic doses of commonly used neuroleptics significantly more frequently presented with transient EEG changes (7% of patients) in relation to the incidence of epileptic attacks (0.1–1.5%). The aim of our study was to verify epileptogenic impact of neuroleptic treatment in the group adolescent patients. Methods: The study included 19 adolescents with chronic neuroleptic therapy and optimal therapeutic doses. None of the patients experienced seizures before therapy. The average age of the patients was 16.5 yrs, the average therapy duration was 3 yrs. Results: 68% of the adolescents had nonspecific EEG findings. 32% had specific (bilateral epileptiform paroxysmal/nonparoxysmal) EEG changes. Half of them, with normal MRI, presented with seizures as a clinical correlate to the EEG changes (0.2% of the population). The greatest epileptogenic potential had olanzapine, chlorpromazine and haloperidol. Conclusion: In our experience, arising from this study, proepileptogenic and proconvulsive effects of neuroleptics were once again confirmed, particularly strong among adolescents, suggesting an important receptor hypersensitivity likely caused by endogenous and biological factors (age, hormonal status, the dynamic body mass, volume changes, etc).

Tardive Tourette-Like Syndrome in a Patient Treated With Paliperidone

Tardive Tourette-Like Syndrome in a Patient Treated With Paliperidone

Possible antioxidant and neuroprotective mechanisms of FK506 in attenuating haloperidol-induced orofacial dyskinesia

Tardive dyskinesia is a serious motor side effect of chronic neuroleptic therapy. The pathophysiology of this disabling and commonly irreversible movement disorder is still obscure. It may be caused by a loss of dopaminergic cells, due to free radicals as a product of high synaptic dopamine levels. Chronic treatment with neuroleptics leads to the development of abnormal oral movements in rats called vacuous chewing movements. Vacuous chewing movements in rats are widely accepted as an animal model of tardive dyskinesia. Chronic haloperidol (1 mg/kg for 21 days) treatment significantly induced vacuous chewing movements and tongue protrusions in rats, and FK506 (Tacrolimus) {[3 S-[3 R*[ E(1 S*,3 S*,4 S*)],4 S*,5 R*,8 S*,9 E,12 R*,14 R*,15 S*,16 R*,18 S*,19 S*,26 aR*]]-5,6,8,11,12,13,14,15,16,17,18,19,24,25,26,26 a-hexadecahydro-5, 19-dihydroxy-3-[2-(4-hydroxy-3-methoxycyclohexyl)-1-methylethenyl]-14, 16-dimethoxy-4,10,12, 18-tetramethyl-8-(2-propenyl)-15, 19-epoxy-3 H-pyrido[2,1- c][1,4] oxaazacyclotricosine-1,7,20, 21(4 H,23 H)-tetrone, monohydrate} dose dependently (0.5 and 1 mg/kg) reduced these haloperidol-induced movements. Biochemical analysis revealed that chronic haloperidol treatment significantly induced lipid peroxidation and decreased the levels of glutathione and of the antioxidant defense enzymes, superoxide dismutase and catalase, in the brains of rats. Co-administration of FK506 dose dependently (0.5 and 1 mg/kg) and significantly reduced the lipid peroxidation and restored the decreased glutathione levels induced by chronic haloperidol treatment. It also significantly reversed the haloperidol-induced decrease in brain superoxide dismutase and catalase levels. The major findings of the present study suggest that oxidative stress-induced neuronal death might play a significant role in neuroleptic-induced orofacial dyskinesia. In conclusion, FK506 could be a useful drug for the treatment of neuroleptic-induced orofacial dyskinesia.

Central administration of the neurotensin receptor antagonist sr48692 attenuates vacuous chewing movements in a rodent model of tardive dyskinesia

Tardive dyskinesia is a movement disorder that develops in 20–30% of patients treated with chronic neuroleptics. Whilst the pathogenesis of tardive dyskinesia remains unclear, altered expression of neuropeptides in the basal ganglia has been implicated in its emergence. The peptide neurotensin is expressed in both dopamine D1 receptor-bearing neurons of the direct striatonigral pathway and dopamine D2 receptor-bearing neurons of the indirect striatopallidal pathway. Increased levels of striatal neurotensin messenger RNA (mRNA) are reported following chronic neuroleptic therapy. Chronic treatment with the typical antipsychotic haloperidol elicits neurotensin immunoreactivity in a large number of striatopallidal and a modest number of striatonigral projection neurons, whilst treatment with the potent dopamine releaser, methamphetamine, induces intense neurotensin immunoreactivity in striatonigral projection neurons. In order to determine whether increased levels of striatal neurotensin mRNA in the direct striatonigral or the indirect striatopallidal pathway play a more influential role in the development of tardive dyskinesia, we explored the effects of a specific neurotensin antagonist in a rodent model (vacuous chewing movements [VCMs] induced by chronic neuroleptics). Three groups of animals received injections of fluphenazine decanoate (25 mg/kg) or its vehicle sesame oil every 3 weeks for at least 18 weeks. They were then surgically implanted with bilateral guide cannulae aimed at the striatum, the substantia nigra pars reticulata, or the globus pallidus respectively. After recovery, animals were infused with 2-[(1-(7-chloro-4-quinolinyl)-5-(2,6-imethoxyphenyl)pyrazol-3-yl)carbonylamino]tricyclo(3.3.1.1. 3.7)decan-2-carboxylic acid (SR48692; 0.25, 0.50, and 1.0 nmol/μl), or its vehicle (10% dimethyl sulfoxide [DMSO] in saline) and observed for 60 min. Intra-striatal, intra-nigral or intra-pallidal infusion of SR48692 attenuated neuroleptic-induced VCMs. These findings lend further support to a role for neurotensin in the development of VCMs but do not clarify which pathway plays a more important role. Thus, treatments that reduce or prevent the effects of increased neurotensin expression and release may be useful in the management of tardive dyskinesia.

Effect of 5-HT 1A and 5-HT 2A/2C receptor modulation on neuroleptic-induced vacuous chewing movements

Tardive dyskinesia is a serious motor side effect of chronic neuroleptic therapy. Chronic treatment or rats with neuroleptics leads to the development of abnormal oral movements called vacuous chewing movements. Vacuous chewing movements in rats are widely accepted as an animal model of tardive dyskinesia. Atypical antipsychotics such as clozapine and rispiridone are associated with a lower incidence of extrapyramidal side effects and tardive dyskinesia. The present study was aimed to explore the role of 5-HT 1A, 5-HT 2A/2C receptors in the expression of neuroleptic-induced orofacial dyskinesia. In the present study rats were chronically (for 21 days) treated with haloperidol (1.5 mg/kg, i.p.) to elicit vacuous chewing movements. The neuroleptic-induced vacuous chewing movements, viz., vertical jaw movements, tongue protrusions and bursts of jaw tremors, were counted during a 5-min observation period. Acute treatment with 8-hydroxy-2-(di- n-propylamino) tetralin (8-OH-DPAT), a 5-HT 1A receptor agonist, dose-dependently (0.05, 0.1 and 0.2 mg/kg, i.p.) reduced the haloperidol-induced vacuous chewing movements and headshakes. Both acute and chronic administration of seganserin, ketanserin and ritanserin, 5-HT 2A/2C receptor antagonists, also reduced haloperidol-induced vacuous chewing movements in a dose-dependent (0.05, 0.1 and 0.2 mg/kg, i.p.) manner. In acute studies a higher dose of ritanserin (1 mg/kg) but not ketanserin (1 mg/kg) increased vacuous chewing movements, whereas a higher dose of seganserin (1 mg/kg) did not have any effect on vacuous chewing movements. All the drugs reduced haloperidol-induced headshakes in a dose-dependent fashion. These findings indicate that the serotonergic system, and particularly 5-HT 1A and 5-HT 2A/2C receptors, may be involved in haloperidol-induced orofacial dyskinesia, and that 5-HT receptors may provide novel targets for the development of drugs that can be used to reverse or prevent the extrapyramidal side effects associated with long-term antipsychotic treatment.

Reversal of neuroleptic-induced orofacial dyskinesia by 5-HT 3 receptor antagonists

Tardive dyskinesia, a syndrome of abnormal, involuntary hyperkinetic movements that occurs during long-term neuroleptic therapy is a major limitation of chronic neuroleptic therapy. The pathophysiology of tardive dyskinesia is still an enigma. The objective of the present study was to elucidate the role of 5-HT 3 receptor involvement in neuroleptic-induced vacuous chewing movements in rats. Rats chronically (for 21 days) treated with haloperidol (1.5 mg/kg, i.p.) significantly developed vacuous chewing movements, as compared to vehicle-treated controls. Both ondansetron and tropisetron dose-dependently (0.25, 0.5 and 1.0 mg/kg, i.p.) reversed the haloperidol-induced vacuous chewing movements. Serotonin acting through 5-HT 3 receptors might play a significant role in the pathophysiology of tardive dyskinesia, and 5-HT 3 receptor ligands can be exploited as novel therapeutic agents for the treatment of tardive dyskinesia.

Excitatory mechanisms in neuroleptic-induced vacuous chewing movements (VCMs): possible involvement of calcium and nitric oxide

Tardive dyskinesia (TD) is a serious motor side-effect of chronic neuroleptic therapy. Chronic treatment with neuroleptics leads to the development of oral abnormal movements in rats known as vacuous chewing movements (VCMs). Vacuous chewing movements in rats have been widely accepted as an animal model of tardive dyskinesia. Chronic blockade of D2 inhibitory dopamine (DA) receptors localized on glutamatergic terminals in the striatum leads to the persistent enhanced release of glutamate that kills the striatal output neurons. The object of the present study was to explore the role of glutamatergic modulation on the neuroleptic-induced VCMs. Rats were chronically (for 21 days) treated with haloperidol (1.5 mg/kg, i.p.) to produce VCMs. The neuroleptic-induced VCMs viz., vertical jaw movements, tongue protrusions and bursts of jaw tremors, were counted during a 5 min observation period. Dizocilpine, a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist, dose dependently (0.02 and 0.05 mg/kg) reduced haloperidol-induced VCMs. Felodipine (5 and 10 mg/kg), an L-type calcium-channel blocker, also significantly reduced the VCM count. N-omega-nitro-L-arginine methyl ester (L-NAME) (25 and 50 mg/kg), a nitric oxide synthase inhibitor, also reduced the VCM count in an L-arginine-sensitive manner. In conclusion, the findings of the present study indicated NMDA receptor involvement in haloperidol-induced VCMs, and also suggested the possible involvement of calcium and nitric oxide in haloperidol-induced VCMs.

Tardive dyskinesia: An update.

Tardive dyskinesia (TD) is a serious motor side effect of chronic neuroleptic therapy. TD is a complex hyperkinetic syndrome consisting of choreiform, athetoid or rhythmic abnormal involuntary movements. The face, mouth and tongue are most frequently involved (orofacial type), but a variety of less frequent motor abnormalities of the upper and lower limbs and of the trunk may also occur. TD usually has a delayed onset and the intensity of the syndrome may fluctuate over time. The most serious aspect of TD is that it may persist for months or years after drug withdrawal and in some patients is irreversible. In spite of the prevalence and known etiology that chronic neuroleptic treatment causes TD, relatively little is known about the primary pathological mechanism underlying the condition. Abnormalities in various neurotransmitter systems have been implicated in the pathophysiology of TD, including the dopaminergic, GABAergic, serotonergic and noradrenergic systems. Recently, excitotoxicity of the glutamatergic system and oxidative stress have received much attention. Three general types of animal models have contributed to our knowledge of TD and can be described as homologous, analogous and correlational models. There are no empirically validated guidelines to follow when choosing a suppressive agent. In general, therapeutic trials have attempted to manipulate the dopaminergic, GABAergic, serotonergic and noradrenergic systems, in part due to theories on the pathophysiology of TD. None of these medications has proven successful in the majority of patients. Much more research is needed in order to increase our understanding of TD and to develop better therapeutics for its treatment. (c) 2001 Prous Science. All rights reserved.

Differential role of dopamine D1 and D2 receptors in isoniazid-induced vacuous chewing movements

Tardive dyskinesia (TD) is a syndrome of potentially irreversible and involuntary hyperkinetic disorders that occurs during chronic neuroleptic therapy and is a major limitation of such therapy. Vacuous chewing movements (VCMs) in rats have been widely accepted as an animal model of tardive dyskinesia. In the present study isoniazid (1, 2 and 5 microM i.c.v.) dose-dependently produced VCMs in rats. The response produced by a 10-microM dose was lower than that of earlier doses but was statistically significant when compared to a saline-treated group. Diazepam (1 and 4 mg/kg i.p.) and progabide (50 and 100 mg/kg i.p.) dose-dependently reversed the isoniazid-induced VCMs. Haloperidol (0.5 and 1 mg/kg i.p.) and SCH-23390 (0.25 and 0.5 mg/kg i.p.) reversed the isoniazid-induced VCMs in a dose-dependent manner. Sulpiride (25 and 50 mg/kg i.p.), a dopamine D2 receptor antagonist, had no effect on isoniazid-induced VCMs. SKF-38393 (10 and 15 mg/kg i.p.) dose-dependently augmented the isoniazid-induced VCMs. Quinpirole 0.02 mg/kg i.p. had no effect on isoniazid-induced VCMs but a higher quinpirole dose (0.05 mg/kg) significantly reduced isoniazid-induced VCMs. Isoniazid (2 microM i.c.v.) produced stereotypy (grooming and rearing) in rats. Haloperidol (0.5 and 1 mg/kg i.p.), SCH-23390 (0.25 and 0.5 mg/kg i.p.) and sulpiride (25 and 50 mg/kg i.p.) decreased the severity of isoniazid-induced stereotypy. SKF-38393 (10 and 15 mg/kg i.p.) dose-dependently augmented the isoniazid-induced grooming behavior more prominently as compared to quinpirole (0.02 and 0.05 mg/kg i.p.); on the other hand quinpirole potentiated isoniazid-induced rearing behavior. In conclusion, the results of the present study demonstrated the differential involvement of dopamine D1 and D2 receptors in isoniazid-induced VCMs.

Effects of subthalamic nucleus lesions in a putative model of tardive dyskinesia in the rat.

The effects of bilateral excitotoxic lesions of the subthalamic nucleus on vacuous chewing movements induced by chronic neuroleptic therapy were examined in the rat. Fluphenazine decanoate (25 mg/kg i.m.q 3 weeks x 24 weeks) induced vacuous chewing movements, as previously described. This response was suppressed to control levels in animals tested 1-3 weeks following bilateral infusion of quinolinic acid (100 nmol/1 microliter per side) into the subthalamic nucleus. Subthalamic nucleus lesions resulted in increased locomotion and sniffing in neuroleptic-naive animals, but these responses were suppressed by concomitant neuroleptic treatment. As vacuous chewing movements induced by chronic neuroleptics are considered to be analogous to tardive dyskinesia in humans, our findings lend further support to the importance of the subthalamic nucleus in the regulation of orofacial movements and suggest that tardive dyskinesia may, in part, be related to altered activity in this structure. This, in turn, suggests that current models of basal ganglia function are inadequate to account for certain pathological states and require re-examination.

Recurrent mandibular dislocation under neuroleptic drug therapy, treated by bilateral eminectomy

Acute mandibular dislocations caused by extrapyramidal syndromes under neuroleptic therapy have often been reported in the literature. However, the success of surgical therapy for recurrent mandibular dislocation in patients under long-term neuroleptic therapy has been discussed controversially. In our opinion, modifications in drug therapy--including the administration of so-called atypical neuroleptics--should be considered before advocating surgery. If the revised therapeutic approach proves to be unsuccessful because of psychotic relapse or persistence of extrapyramidal symptoms, good operative results may be achieved by bilateral eminectomy as reported on three psychiatric patients in this paper. In order to avoid postoperative subluxation and internal derangement due to increased muscular tension under chronic neuroleptic therapy, as much bone as possible should be removed when performing eminectomy.

Psychosis as the initial manifestation of adult-onset Niemann-Pick disease type C

Niemann-Pick disease type C (NPC) is a neurometabolic genetic disorder that is distinguished from Niemann-Pick disease by its later onset, more insidious progression, variable visceromegaly, and abnormalities of intracellular cholesterol metabolism. We describe a patient who presented with an 8-year history of psychosis requiring chronic neuroleptic therapy for a presumed diagnosis of schizophrenia. He was subsequently diagnosed with NPC as the emerging features of dementia, ataxia, dysarthria, and vertical supranuclear ophthalmoplegia were recognized. The characteristic features of adult-onset NPC and the obstacles to early diagnosis are reviewed.

Persistent catalepsy associated with severe dyskinesias in rats treated with chronic injections of haloperidol decanoate.

Patients who develop persistent parkinsonism while on chronic neuroleptic therapy may be predisposed towards the development of tardive dyskinesia (TD). We investigated this issue in an animal model of TD by examining the association between catalepsy and the syndrome of neuroleptic-induced vacuous chewing movements (VCMs). VCMs were measured every 3 weeks for 33 weeks while rats received injections of haloperidol decanoate. Catalepsy was measured after the second through the seventh injections of the depot neuroleptic. There were no correlations between the severity of catalepsy scores after the second or third injections of haloperidol and the severity of the overall VCM syndrome. However, the severity of the catalepsy score following the third through seventh injections of haloperidol strongly correlated with the concurrent number of VCMs. Persistent high catalepsy scores across the six catalepsy rating sessions were strongly associated with the development of persistent severe VCMs. These findings suggest that, to the extent that persistent parkinsonian signs in humans are associated with a propensity towards the development of TD, the VCM syndrome in rats is at least a partially faithful animal model of this relationship.

Evidence of lipid peroxidation in patients taking neuroleptic drugs

This study investigated the effect of chronic neuroleptic therapy on hepatic glutathione concentration in relation to lipid peroxidation. Hepatic malondialdehyde (MDA) and glutathione (GSH) concentrations were measured in liver biopsies from a group of patients receiving chronic psychotropic drug therapy. The results were compared with values obtained from a selected group of controls and correlated to liver histology and blood biochemistry. Patients taking neuroleptics exhibited increased hepatic MDA and decreased total GSH levels when compared with controls. The reduction of GSH was accompanied by a 25% increase in oxidized glutathione (GSSG) concentrations. In addition, a positive correlation between liver MDA and GSSG concentrations was observed in the group receiving neuroleptic therapy. The study results suggest that an increased lipid peroxidation may represent a contributory mechanism for neuroleptic drug toxicity.

Persistent and Progressive Parkinsonism after Discontinuation of Chronic Neuroleptic Therapy

Drug-induced parkinsonism is usually reversible, except in a small percentage of elderly patients. We describe two relatively young patients, who developed drug-induced parkinsonism during chronic treatment with neuroleptics for a psychotic disorder. Parkinsonism persisted, and markedly and progressively deteriorated after discontinuation of neuroleptic drugs. One patient had tremor as the most prominent sign and the other had mainly an akinetic-rigid syndrome. Neither had ever developed tardive dyskinesia. Both responded to levodopa therapy. Persistent drug-induced parkinsonism in our, and other reported on, elderly patients may be due to unmasking of preexisting subclinical idiopathic Parkinson's disease by neuroleptics. Theoretically, these drugs may precipitate degeneration of vulnerable, nigrostriatal neurons by generating cytotoxic free radicals or by attrition, due to accelerated neuronal firing rates.

Risk Factors for Neuroleptic-Induced Movement Disorders

Chronic neuroleptic therapy may be associated with the development of diverse movement disorders including Tardive dyskinesia (TD), Parkinsonism, dystonia, and akathisia in a subset of schizophrenic patients. It is presently unknown why only a proportion of neuroleptic-treated patients develop these movement disorders. In the following communication, we present a series of studies which demonstrate that the development of these movement disorders may be facilitated by certain risk factors including disturbances in pineal melatonin functions, diabetes mellitus, cognitive deficits, suicidal behavior, and disturbances in the functions of the choroid plexus. Recognition of these biological factors may prove useful in: (a) further understanding of the pathophysiology of these disorders, and (b) identifying patients at risk for these movement disorders.

Diltiazem suppresses quinpirole-induced oral stereotypies in haloperidol withdrawn rats

Pucilowski, Olgierd and Burr Eichelman: Diltiazem suppresses quinpirole-induced oral stereotypies in haloperidol withdrawn rats. Prog. Neuro-Psychopharmacol. & Biol. Psychiat. 1991, 15 (5): 717–722. 1. 1. Tardive dyskinesia (TD) is one of the most serious untoward effects of chronic neuroleptic therapy. Dopaminergic receptor sensitization is assumed to be involved in its pathogenesis. 2. 2. Male Wistar rats were administered (b.i.d.) intragastrically haloperidol (2 mg/kg), diltiazem (5 mg/kg), diltiazem plus haloperidol, and water (controls), for 21 days. 3. 3. Forty eight hours after withdrawal the rats were injected ip with 0.3 mg/kg of quinpirole and observed for stereotypic behaviors (rearing, grooming, licking, and tongue protrusions). 4. 4. There was a significant overall between-group difference in the duration of grooming and the number of tongue protrusions. The haloperidol withdrawn rats scored markedly higher than control and diltiazem alone treated rats. 5. 5. Conjoint treatment with diltiazem and haloperidol prevented the increase of tongue protrusion episodes. 6. 6. We conclude that concurrent diltiazem and haloperidol administration can prevent the occurrence of some behavioral manifestations of dopaminergic receptor supersensitivity, including a lingual dyskinesia.

Recognition and Differential Diagnosis of Tardive Dyskinesia

Tardive dyskinesia (TD) is a consequence of chronic neuroleptic therapy. It is an irregular stereotyped movement disorder that is usually choreic in appearance, and is subject to temporary volitional control. Dystonia, akathisia, and tics are uncommon variants of the classic tardive syndrome. Characteristic clinical features including amelioration by action, augementation by distraction, partial volitional suppressibility, and lack of subjective distress help differentiate TD from other movement disorders such as resting tremor, Huntington's disease, spontaneous dyskinesias, and abnormal movements accompanying psychiatric illnesses.

Antiepileptic drugs in the treatment of neuroleptic-induced supersensitivity psychosis

1. Supersensitivity psychosis (SSP) has emerged as a potential side-effect of long term neuroleptic therapy similar to tardive dyskinesia. 2. Five schizophrenic patients with SSP and considered to be drug-resistant were treated with antiepileptic drugs. All 5 improved initially and in three the improvement was maintained at follow-up. 3. The proposed mechanism of action of the antiepileptic drugs is through correcting a pharmacological kindling effect in the limbic system which results from chronic neuroleptic therapy.

The Relationship of Pineal Calcification to Subtypes of Tardive Dyskinesia in Bipolar Patients

Recent studies have suggested that bipolar patients may be at high risk for developing tardive dyskinesia (TD) if exposed to chronic neuroleptic therapy. It has been suggested that reduced melatonin secretion may favor the development of TD in bipolar and schizoaffective patients. Since pinealectomized rats have been reported to develop increased incidence and severity of abnormal chewing movements, and as depression is associated with reduced melatonin secretion, the increased risk of TD in bipolar patients may be associated with diminished melatonin secretion. Evidence suggestive of an inverse correlation between pineal calcification and reduced melatonin secretion, led me to study the relationship between pineal calcification on CT scan and the severity of axial (truncal) and limb and orofacial dyskinesias in bipolar patients with TD. The incidence of pathologically enlarged pineal calcifications (i.e., greater than 1 cm in diameter) in the bipolar patients was 25 times greater than the reported incidence in the literature among nonpsychiatric patients. In addition, there was a significant difference in scores of axial dyskinesias between patients with pineal calcification of less than 1 cm in diameter compared to those with pineal calcification of greater than 1 cm in diameter (F = 3.24; p = .04, one-way ANOVA). There was no significant association between scores of limb and orofacial dyskinesias and pineal calcification. These findings suggest a meaningful association between the presence of enlarged pineal calcification, and axial dyskinesias in bipolar patients. Further studies using direct plasma melatonin measurements are required to more precisely define the association between TD and melatonin secretion in bipolar patients.