Dystonia caused

Burke, R., Fahn, S., Jankovic, J., Marsden, C. D., Lang, A. E., Gollomp, S., et al. (1982). Tardive dystonia Late-onset and persistent dystonia caused by antipsychotic drugs. 

Burke RE, Fahn S, Jankovic J, Marsden CD, Lang AE, Gollomp S, Ilson J. Tardive dystonia late-onset and persistent dystonia caused by antipsychotic drugs. Neurology 1982 32(12) 1335-46. 

Alevizos B, Papageorgiou C, Christodoulou GN. Acute dystonia caused by low dosage of olanzapine. J Neuropsychiatry Clin Neurosci 2003 15 241. 

Goodchild, RE. and Dauer, W.T. (2004) Mislocalization to the nuclear envelope an effect of the dystonia-causing torsinA mutation. Proc. Natl Acad. Sci. U.S.A. 101, 847-852. 

Reduce EPS dysfunction (pseudo-Parkinsonism, dystonias) caused by DA receptor antagonists. Diphenhydramine IM is especially useful in acute dystonias. 

CNS Scopolamine is standard therapy for motion sickness this drug is one of the most effective agents available for this condition. A transdermal patch formulation is available. Benztropine, biperiden. and trihexyphenidyl are representative of several antimuscarinic agents used in parkinsonism. Although not as effective as levodopa (see Chapter 28), these agents may be useful as adjuncts or when patients become unresponsive to levodopa. Benztropine is sometimes used parenterally to treat acute dystonias caused by antipsychotic medications. 

Botulinum neurotoxins are widely used as therapeutic agents to cause reduction or paralysis of skeletal muscle contraction. They are used to treat cervical dystonia, which causes regional involuntary muscle spasms often associated with pain. Moreover, they are used in strabism, blepharospasm, hemifacial spasm, and... 

Among the most significant adverse reactions associated with the antipsychotic dm are the extrapyramidal effects. The term extrapyramidal effects refers to a group of adverse reactions occurring on the extrapyramidal portion of the nervous system as a result of antipsychotic drains. This part of the nervous system affects body posture and promotes smooth and uninterrupted movement of various muscle groups. Antipsychotics disturb the function of the extrapyramidal portion of the nervous system, causing abnormal muscle movement. Extrapyramidal effects include Parkinson-like symptoms (see Chap. 29), akathisia, and dystonia (see Display 32-1). 

Phenothiazines may cause sedation, orthostatic hypotension, and extrapyramidal symptoms (EPS) such as dystonia (involuntary muscle contractions), tardive dyskinesia (irreversible and permanent involuntary movements), and akathisia (motor restlessness or anxiety).1,21,22 Chronic phenothiazine use has been associated with EPS, but single doses have also caused these effects.23... 

Side effects can also occur quickly after a single dose of a medication. For example, some antidepressants (e.g., selective serotonin reuptake inhibitors) can cause nausea, stomach upset, loose stools, and even diarrhea. Likewise, some anti-psychotics (e.g., haloperidol (Haldol)) can cause unpleasant or painful muscle spasms called dystonias. All of these side effects can occur within minutes or hours of taking a single dose of the medication. These side effects are also a result of the direct effects of the medication in the synapse. 

Domperidone is used in combination with antiparkinsonian drugs to counteract the nausea and vomiting caused by the latter. Since it does not readily cross the blood-brain barrier, it is not associated with extra-pyramidal effects and is less likely to cause dystonia than metoclopromide and phenothiazines. 

Extrapyramidal reactions include parkinsonism, acute muscular dystonias, akathisia, tardive dyskinesia and malignant neuroleptic syndrome. They can also cause hypersensitivity reaction including cholestatic jaundice, skin rash, urticaria, photosensitivity and contact dermatitis. There is also blue pigmentation of skin, lenticular opacities on prolonged use of drug. 

Neuroleptics may also cause blepharospasm, which is a forcible closure of the eyelids and when severe can interfere with activities such as driving this condition can also be socially disabling and disfiguring. In addition, there are a few cases indistinguishable from idiopathic Meighs syndrome, which presents with blepharospasm and oromandibular dystonia (470). Of interest, clozapine has been reported to be beneficial for these symptoms. 

Ichinose H, Ohye T, Takahashi E, Seki N, Hori T, Segawa M, Nomura Y, Endo K, Tanaka H, Tsuji S, Fujita K, Nagatsu T (1994) Hereditary progressive dystonia with marked diurnal fluctuation caused by mutation in the GTP cyclohydrolase I gene. Nature Genet 8 236-241... 

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