Antipsychotics akathisia

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). 

Extrapyramidal symptoms (EPS) Adverse effects of medications such as antipsychotics. EPS include dystonia (involuntary muscle contractions), tardive dyskinesia (repetitive, involuntary movements), parkinsonian symptoms (akinesia and tremors), and akathisia (motor restlessness or anxiety). 

Akathisia The motor restlessness often noted as a side effect of long-term administration of typical antipsychotic drugs. 

The answer is c. (Hardman, pp 414-4163) Unwanted pharmacologic side effects produced by phenothiazine antipsychotic drugs (e.g., perphenazine) include Parkinson-like syndrome, akathisia, dystonias, galactorrhea, amenorrhea, and infertility. These side effects are due to the ability of these agents to block dopamine receptors. The phenothiazines also block muscarinic and a-adrenergic receptors, which are responsible for other effects. 

Treatment with AChs is disappointing, and reduction in antipsychotic dose may be the best intervention. Another alternative is to switch to an SGA, although akathisia occasionally occurs with the SGAs. Quetiapine and clozapine appear to have the lowest risk for causing akathisia. 

Infrequently, SSRIs produce dystonic reactions, which are intense mnscle spasms nsnally of the face and neck. They may cause akathisia, a restless inability to sit still. Dystonic reactions and akathisia are more commonly side effects of the dopamine-blocking antipsychotics. It is believed that SSRIs prodnce these effects because increasing 5HT activity tends to decrease dopamine. When these side effects occur, the SSRI should be switched to another antidepressant. 

Antipsychotics also have a troublesome side effect burden that includes an often-irreversible movement disorder known as tardive dyskinesia (TD). Other side effects include so-called parkinsonism, dystonic reactions (i.e., abrupt onset of muscle spasms), akathisia (an uncomfortable sense of motoric restlessness), sedation, weight gain, dizziness, dry mouth, and constipation among others. These side effects, in particular the risk for TD, limit the usefulness of antipsychotics in the treatment of ADHD, and at this time the typical antipsychotics cannot be considered a reasonable monotherapy in uncomplicated ADHD. 

Akathisia. This is a restless inability to sit still. It is an extremely nnpleasant sensation that can arise when a patient is treated with an antipsychotic drng (this is... 

In addition to parkinsonism, another extrapyramidal side effect is the so-called acute dystonic reaction in which muscles (usually of the face or neck) go into an acute spasm. A dystonic reaction is painful and unpleasant, usually occurs early in treatment, and sometimes occurs after the very first dose of an antipsychotic. Another extrapyramidal symptom is akathisia, a restless inability to relax and sit still. Akathisia can range from a mild restlessness to extreme agitation. Rarely, patients have been known to attempt suicide during severe episodes of akathisia. It is easy to overlook akathisia, because it can easily be mistaken for a worsening of psychosis or anxiety. 

Akathisia. Akathisia is yet another extrapyramidal side effect. The approach to treatment depends on its severity. For mild restlessness, dose reduction or dividing the daily dose to reduce the peak plasma levels of the medication may be successful. If mild akathisia remains a problem, it may be preferable to add a medication to treat this side effect or preferably switch to another antipsychotic or antidepressant that is less likely to cause akathisia. 

Most antipsychotics and especially the piperazines and the butyrophenones can cause extrapyra-midal symptoms. Blockade of dopamine receptors mainly in the corpus striatum is held responsible for these extrapyramidal effects. They may become manifest as a variety of clinical symptoms and it should be noted that within 24 8 hours after the beginning of treatment acute dystonic reactions like torticollis, facial grimacing and opisthotonos may occur. Parkinsonism-like symptoms such as bradyki-nesia, rigidity and tremor occur after weeks or months of therapy and are more common in the elderly. Motor restlessness, i.e. akathisia, also mostly occurs not before weeks or months after starting therapy. The tendency of an antipsychotic agent to produce extrapyramidal symptoms appears to be inversely related to its ability to block cholinergic receptors. 

In addition to the somatic side-effects of neuroleptics, there are a number of important psychiatric side-effects, such as demotivation or indifference (a direct effect of most drugs, actually part of the definition of the neuroleptic effect). This may mimic the negative features of the illness and may lead to prescriptions of an antidepressant when a reduction in dose or change of antipsychotic may be more appropriate. A second key problem is anxious activation or akathisia. This dose-dependent dysphoric state may lead to an apparent worsening in the clinical picture and accordingly an increase in antipsychotic dose rather than decrease and may be so intolerable as to lead on to suicide. 

Two extrapyramidal conditions, acute dystonia and akathisia, occur early during treatment, while parkinsonism tends to evolve gradually over days to weeks. All three reactions occur most commonly with the high-potency antipsychotics (Table 34.1) and are related to high Dz-receptor occupancy. Acute dystonia, which occurs in about 5% of patients on antipsychotic therapy, consists of uncontrollable movements and distortions of the face, head, and neck. It can be treated with centrally acting an-timuscarinic agents, such as benztropine, while antipsychotic therapy is temporarily discontinued. When this reaction subsides, the anticholinergic can be withdrawn. 

It is recommended that neurological side effects be monitored carefully throughout the course of antipsychotic treatment. Rating scales can assist in monitoring for EPS and the involuntary movements seen in tardive dyskinesia. These include the Neurological Rating Scale (Simpson and Angus, 1970), the Barnes Akathisia Scale (Barnes, 1989), and the Abnormal Involuntary Movement Scale ([AIMS] National Institute of Mental Health, 1985). 

EPS include acute dystonic reactions, parkinsonian syndrome, akathisia, tardive dyskinesia, and neuroleptic mahgnant syndrome. Although high-potency conventional antipsychotics are more hkely than low-potency conventional antipsychotics to cause EPS, all first-generation antipsychotic drugs are equally hkely to cause tardive dyskinesia. The atypical antipsychotics cause suhstantially fewer EPS, which is one reason that they are recommended as first-line agents. 

Lorazepam (2 mg i.m.) was found to be equivalent to haloperidol (5 mg i.m.) either alone or when added to ongoing antipsychotic treatment, and significantly reduced the likelihood of akathisia and dystonia (167). In the treatment of acute mania, lorazepam has also been reported useful as an adjunct to lithium, as well as antipsychotics (157, 163, 165, 168, 169). 

Nausea and sometimes vomiting may occur because of activation of 5-HT3 receptors. Tolerance generally develops to this within 7-10 days. A syndrome of agitation, which seems identical to the akathisia sometimes induced by antipsychotic drugs, may occur early in treatment in a small proportion of patients and is usually an indication to stop the SSRI. 

Most antipsychotic drugs cause unpleasant subjective effects in nonpsychotic individuals. The mild to severe EPS, including akathisia, sleepiness, restlessness, and autonomic effects are unlike any associated with more familiar sedatives or hypnotics. Nevertheless, low doses of some of these drugs, particularly quetiapine, are used to promote sleep onset and maintenance, although there is no approved indication for such usage. 

Akathisia A feeling of extreme motor restlessness and an inability to sit still may occur because of antipsychotic drug therapy. 

Amoxapine is a metabolite of the antipsychotic drug loxapine and retains some of its antipsychotic action and dopamine receptor antagonism. A combination of antidepressant and antipsychotic actions might make it a suitable drug for depression in psychotic patients. However, the dopamine antagonism may cause akathisia, parkinsonism, amenorrhea-galactorrhea syndrome, and perhaps tardive dyskinesia. 

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