Hyperkinetic movements

Parkinson s disease (PD) is a hypokinetic movement disorder 766 Huntington s disease is a hyperkinetic movement disorder 771 Wilson s disease is a disease of copper accumulation 773 Dystonia is characterized by sustained muscle contractions 775 Many drugs and toxins induce movement disorders 776... 

Kenney C et al Long-term tolerability of tetrabenazine in the treatment of hyperkinetic movement disorders. Mov Disord 2007 22 193.[PMID 17133512]... 

Hyperactivity of dopamine in the nigrostriatal pathway is thought to underlie various hyperkinetic movement disorders, such as chorea, dyskinesias, and tics. Chronic blockade of dopamine 2 receptors in this pathway may result in a hyper-... 

FIGURE 10-12. The nigrostriatal dopamine pathway is part of the extrapyramidal nervous system and plays a key role in regulating movements. When dopamine is deficient, it can cause parkinsonism with tremor, rigidity, and akinesia/bradykinesia. When DA is in excess, it can cause hyperkinetic movements such as tics and dyskinesias. 

Worse yet, if these D2 receptors in the nigrostriatal DA pathway are blocked chronically (Fig. 11—5), they can produce a hyperkinetic movement disorder known as tardive dyskinesia. This movement disorder causes facial and tongue movements such as constant chewing, tongue protrusions, and facial grimacing, as well as limb movements, which can be quick, jerky or choreiform (dancing). Tardive dyskinesia is thus caused by long-term administration of conventional antipsychotics and is... 

FIGURE 11-5. Long-term blockade of dopamine 2 receptors by dopamine 2 antagonists in the nigrostriatal dopamine pathway may cause these receptors to up-regulate. A clinical consequence of this may be the hyperkinetic movement disorder known as tardive dyskinesia. This up regulation may be the consequence of the neuron s futile attempt to overcome drug-induced blockade of its dopamine receptors. 

Potentially irreversible, late onset, extrapyramidal hyperkinetic movement disorder often associated with the long-term administration of neuroleptics. Abnormal movements generally involve the mouth, lips and tongue. 

It appears, therefore, that D-1 blockade is not relevant to the antipsychotic effect or suppression of hyperkinetic movement disorders. 

In an attempt to shed light on the mechanism by which neuroleptics induce extrapyramidal reactions, Bishnoi et al. (2007) chronically administered haloperidol (1 mg/kg) and chlorpromazine (5 mg/kg) to rats, resulting in a time-dependent increase in orofacial hyperkinetic movements. They found a corresponding time-dependent decrease in extracellular levels of norepinephrine, dopamine, and serotonin in various cortical and subcortical regions of the brain. 

Lindemann S, Lessenich A, Ebert U, Loscher W (2001) Spontaneous paroxysmal circling behavior in the ci2 rat mutant Epilepsy with rotational seizures or hyperkinetic movement disorder Exp Neurol 172 437-445. 

Since the gamut of the clinical pharmacology of tics is broad, it is often difficult to differentiate tics from other hyperkinetic movement disorders. Of 373 cases of Gilles de la Tourette syndrome, 18 had both tics and other abnormal movements 12 were secondary to neuroleptic drug treatment (167). Akathisia was the most common movement disorder. 

Kompoliti K, Goetz CG. Hyperkinetic movement disorders misdiagnosed as tics in Gilles de la Tourette syndrome. Mov Disord 1998 13(3) 477-80. 

Tardive tremor is a hyperkinetic movement disorder associated with chronic neuroleptic drug treatment. It was first described in 1991 as a symmetrical tremor, of low frequency, present at rest and during voluntary movements but most prominent during maintenance of posture, and often accompanied by tardive dyskinesia. Tetrabenazine is the current treatment. Sequential responsiveness to both tetrabenazine and clozapine has been reported (97). 

Trade names Nitoman (Lifehealth LTD) Xenazine Indications Hyperkinetic movement disorders Huntington s chorea, hemiballismus, senile chorea, Tourette syndrome, and tardive dyskinesia... 

Failure to reduce hyperkinetic movements in HD patients (reviewed by Consroe 1998)... 

Tourette s syndrome (TS) is a hyperkinetic movement disorder with symptoms of sudden, rapid and brief, recurrent, stereotyped motor movements or sounds (tics) and can range from mild to severe. TS is commonly treated with dopamine antagonists such as haloperidol, which may be effective but has significant adverse side effects and is ineffective in up to 30% of cases. While the etiology is not known it is proposed that, unlike PD, TS represents a disorder of excess dopamine transmission in the striatum (Shapiro et al., 1989 Wolf et al., 1996), either through dopamine excess or receptor hypersensitivity. 

Muscle spasms, particularly those associated with multiple sclerosis or dystonia, may improve significantly with cannabinoid therapy. However, while CBD has been found effective in combination with standard therapy (which was insufficient to adequately control dystonic motor symptoms without CBD), both A -THC and marijuana were found to have untoward side-effects at the doses required to reduce muscle tone. Additionally, CBD may prove beneficial for other hyperkinetic movement disorders such as drug-induced dystonia and possibly tardive dyskinesia. 

Nervous system Tetrabenazine inhibits vesicular monoamine transporter 2, leading to depletion of dopamine and other monoamines in the central nervous system. In a retrospective chart review, 448 patients who had used tetrabenazine between 1997 and 2004 (mean age at onset of the movement disorder, 43 years 42% men) were treated for a variety of hyperkinesias, including tardive dyskinesia (n = 149), dystonia (n = 132), chorea (n = 98), tics (n = 92), and myoclonus (n = 19) [68"]. They took treatment for a mean of 2.3 years and efficacy was sustained in most cases. Common adverse effects included drowsiness (25%), parkinsonism (15%), depression (7.6%), and akathisia (7.6%). Although it has repeatedly been observed that tetrabenazine alleviates hyperkinetic movements, it can worsen parkinsonism [69 ]. 

Susceptibility factors Age In a review of tetrabenazine therapy in 31 children with hyperkinetic movement disorders refractory to other medications, adverse effects were similar to those in adults however, the children had a lower incidence of drug-induced parkinsonism [7 ]. 

Jain S, Greene PE, Frucht SJ. Tetrabenazine therapy of pediatric hyperkinetic movement disorders. Mov Disord 2006 21 (11) 1966-72. 

A patient experienced symptoms of delirium and hyperkinetic movement disorders shortly after initiating treatment with cyclobenzaprine and oxycodone [26 ]. 

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