Pseudoparkinsonism

Patients with pseudoparkinsonism may have any of four cardinal symptoms ... 

The onset of symptoms is usually 1 to 2 weeks after initiation of antipsychotic therapy or dose increase. The risk of pseudoparkinsonism with SGAs is low except in the case of risperidone in doses greater than 6 mg/day. 

Acute dystonias occur immediately after neuroleptization and are manifested by motor impairments, particularly in the head, neck, and shoulder region. After several days to months, a parkinsonian syndrome (pseudoparkinsonism) or akathisia (motor restlessness) may develop. All these disturbances can be treated by administration of antiparkin-son drugs of the anticholinergic type, such as biperiden (i.e., in acute dystonia). As a rule, these disturbances disappear after withdrawal of neuroleptic medication. Tardive dyskinesia may become evident after chronic neuroleptization for several years, particularly when the drug is discontinued. It is due to hypersensitivity of the dopamine receptor system and can be exacerbated by administration of anticholinergics. 

Trihexyphenidyl, benztropine In parkinsonism and drug-induced pseudoparkinsonism Scopolamine In vestibular disorders such as motion sickness... 

Parkinsonism and pseudoparkinsonism Parkinsonism or pseudoparkinsonism induced by neuroleptic drugs is clinically indistinguishable from postencephalitic... 

Pseudoparkinsonism Akathisia Sedation Antipsychotics Sedative/hypnotics Tricyclic antidepressants Muscle relaxants... 

Antiparkinsonism-anticholinergic medication treats pseudoparkinsonism and the early stages of Parkinson s disease. They are prescribed for pseudoparkinsonism. Pseudoparkinsonism is parkinsonism-like side effects of the antipsychotic medication phenothiazines. Antiparkinsonism-anticholinergic medication is combined with levodopa to control parkinsonism. 

Amoxapine, the demethylated metabolite of loxapine, has intermediate sedative and anticholinergic potency. Because of its post-synaptic receptor DA-blocking effects, extrapyramidal side effects, including pseudoparkinsonism, dystonia, akathisia, and tardive dyskinesia have been reported. Amoxapine offers no advantage over standard TCAs or other antidepressants. 

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