Neuroleptics extrapyramidal symptoms

Trihexyphenidyl (Artane) and benztropine (Cogentin) are prescription drugs used in the treatment both of Parkinson s disease and the extrapyramidal side effects produced by neuroleptic medication. They are occasionally abused for their mind-altering properties, which occur at toxic doses (Perry et al. 1978). Abusers often try to obtain these drugs by false representation of extrapyramidal symptoms, which are claimed to result from the use of phenothi-azines or other neuroleptics (Rubinstein 1978). 

Areca may interact adversely with antipsychotic medications (Deahl 1989). Two cases have been reported of schizophrenic patients who were taking neuroleptics and developed severe extrapyramidal symptoms after areca chewing. Given the functional antagonism between dopamine and acetylcholine in the striatum, it is likely that arecoline amplified the dyskinetic effect of neuroleptic medications. 

Extrapyramidal symptoms (EPS) Dystonic reactions develop primarily with the use of traditional antipsychotics. EPS has occurred during the administration of haloperidol and pimozide frequently, often during the first few days of treatment. Neuroleptic malignant syndrome (NMS) A potentially fatal symptom complex sometimes referred to as NMS has been reported in association with administration of antipsychotic drugs. Clinical manifestations of NMS are hyperpyrexia, muscle rigidity, altered mental status, and evidence of autonomic instability (irregular pulse or blood pressure, tachycardia, diaphoresis, cardiac dysrhythmia). Additional signs may include elevated creatine phosphokinase, rhabdomyolysis, and acute renal failure. 

Extrapyramidal symptoms and neuroleptic malignant syndrome occur rarely. 

Anticholinergic drugs are prescribed to people on neuroleptics to reduce extrapyramidal symptoms and they are thought to impair cognitive function. 

The neuroleptics show variable absorption after oral administration. These agents readily pass into the brain, have a large volume of distribution, bind well to plasma proteins, and are metabolized to many different substances by the P-450 system in the liver. Fluphenazine decanoate and haloperidol decanoate are slow release (up to 3 weeks) formulations of neuroleptics, administered by intramuscular injection. These drugs are increasingly used in treating outpatients and individuals who are noncompliant. However, about 30% of these patients develop extrapyramidal symptoms. The neuroleptic drugs produce some tolerance but little physical dependence. 

Most of the neurological disorders associated with the neuroleptics fall into the category of extrapyramidal reactions or extrapyramidal symptoms, and are often designated EPS. The extrapyramidal system of the brain is an extensive, complex network that moderates and adjusts motor... 

The neuroleptics produce a variety of acute, temporary neurological disorders referred to as extrapyramidal symptoms (EPS) in the great majority of patients. As described in chapter 3, drug-induced parkinsonism is one... 

Krausz, M., Moritz, S., Naber, D., Lambert, M., Andresen, B. (1999). Neuroleptic-induced extrapyramidal symptoms are accompanied by cognitive dysfunction in schizophrenia. European Psychiatry, 14, 84-88. 

Extrapyramidal symptoms (including akathisia, dystonia, dyskinesia, tardive dyskinesia, parkinsonism, and brux-ism) have been reported in association with SSRIs, especially in the presence of predisposing factors (SEDA-14, 14 12). Current data suggest that SSRIs should be used with caution in patients with parkinsonism (see the monograph on fluoxetine). Concomitant treatment with neuroleptic drugs and high concentrations of SSRIs seems to predispose to extrapyramidal symptoms. Elderly patients and women are also at increased risk. 

There have been reports of neuroleptic malignant syndrome precipitated by promethazine 100 mg/day to treat neuroleptic drug-induced extrapyramidal symptoms and lorazepam 6 mg/day to treat agitation (349), after the addition of intramuscular haloperidol 23 mg to atypical neuroleptic drugs (350), and in other instances in children and adolescents (351). 

Heck AH, Haffmans PM, de Groot IW, Hoencamp E. Risperidone versus haloperidol in psychotic patients with disturbing neuroleptic-induced extrapyramidal symptoms a double-blind, multi-center trial. Schizophr Res 2000 46(2-3) 97-105. 

Maurer I, Zierz S, Moller HJ, Jerusalem F. Neuroleptic associated extrapyramidal symptoms. Br J Psychiatry 1996 167 551-2. 

Suenaga T, Tawara Y, Goto S, Kouhata SI, Kagaya A, Horiguchi J, Yamanaka Y, Yamawaki S. Risperidone treatment of neuroleptic-induced tardive extrapyramidal symptoms. Int J Psychiatry Chn Pract 2000 4 241-3. 

Although quetiapine seems to cause a lower incidence of extrapyramidal symptoms, a case of neuroleptic malignant syndrome has been described (9). 

In order to limit the risk of extrapyramidal symptoms, the authors suggested that the dose of the oral neuroleptic drug should be reduced or omitted in the days after the injection, and that attention should be paid to the half-life of any other depot drug that has previously been given. 

Hypersalivation or sialorrhea has been reported with all neuroleptic drugs, and has been associated with risperidone as one of the most frequently mentioned adverse effects in patients with disturbing extrapyramidal symptoms during previous neuroleptic drug treatment (SEDA-25, 68). Hypersalivation is a troublesome adverse effect that can contribute to non-adherence to therapy, but it can be treated with clonidine. 

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