Risperidone atypical antipsychotic medications

Risperidone, a novel benzisoxazole derivative, is an atypical antipsychotic medication that combines dopamine D2 receptor antagonism with potent 5-HT2 receptor antagonism. Risperidone has a higher affinity for dopamine D2 receptors than does clozapine. Risperidone also antagonizes dopamine Dj and D4 receptors, aj- and a2-adrenergic receptors, and histamine Hj receptors. Although the optimal dose of risperidone in North American trials was 6 mg/day, subsequent clinical experience has indicated that most patients do well at lower doses of 3-6 mg/day, and elderly patients may require doses as low as 0.5 mg/day. Unlike other atypical antipsychotics. 

Other, chemically distinct dopamine blockers were then developed, such as thiothixene, haloperidol, loxapine, molindone, and pimozide. All of these antipsychotics are potent dopamine blockers and collectively were called neuroleptics because they inadvertently cause certain neurological side effects (discussed below). More recently, atypical antipsychotic medications have been developed (clozapine and risperidone), which are effective antipsychotics yet are weak dopamine blockers and cause minimal neurological side effects. This group is discussed separately below. 

At present there are several medications that have been approved that involve the neurochemical serotonin. The first two medications are clozapine and risperidone and the two newer medications are Seroquel and Zyprexa. To date, these medications have been termed the atypical antipsychotic medications, because they are effective in reducing symptoms of schizophrenia and are less likely to cause extrapyramidal side effects than the other antipsychotic medications (Karper Krystal, 1996). 

Social workers need to be aware of the other atypical antipsychotic medications, such as risperidone, olanzipine and quentiapine. Risperidone (Risperdal) was introduced as the first official atypical antipsychotic medi-... 

First, initiate and/or optimize mood-stabilizing medication lithium3 or valproate3 or atypical antipsychotic (e.g., olanzapine, quetiapine, risperidone)... 

First, optimize current mood stabilizer or initiate mood-stabilizing medication lithium,0 valproate,0 or carba-mazepine0 Consider adding a benzodiazepine (lorazepam or clonazepam) for short-term adjunctive treatment of agitation or insomnia if needed Alternative medication treatment options carbam-azepine0 if patient does not respond or tolerate, consider atypical antipsychotic (e.g., olanzapine, quetiapine, risperidone) or oxcarbazepine. 

Choice of a Mood Stabilizer. With the advance of atypical antipsychotics and an ever-expanding list of anticonvulsants, the number of medications reported to treat acute mania and hypomania continues to grow. In fact, all of the atypical antipsychotics, olanzapine, quetiapine, risperidone, ziprasidone, and aripiprazole have FDA approval for the treatment of acute mania. Long-term protection against future episodes of illness has also been demonstrated with several of these agents, which can influence the choice of initial therapy. 

Atypical antipsychotics may be helpful in managing the delusions and agitated behavior that can accompany dementia. These medications, include risperidone (Risperdal), quetiapine (Seroquel), ziprasidone (Geodon), aripiprazole (Abilify), and olanzapine (Zyprexa). All antipsychotics, typical and atypical, appear to increase the risk of death in patients with dementia and psychosis. This appears as a warning in the package inserts of the newer drugs. A prudent approach is to discuss this risk with the caregiver, use the lowest effective dose, and monitor for effectiveness. 

We prefer low doses of atypical antipsychotics as a first-line treatment. In this way, the threat of extrapyramidal symptoms is largely avoided without having to use a second anticholinergic medication to offset antipsychotic side effects. Risperidone 0.25-0.5mg/day, olanzapine 2.5mg/day, quetiapine 25mg/day, ziprasidone 20mg/day, or aripiprazole 2.5-5mg/day are reasonable starting doses. The typically higher doses used to treat schizophrenia are usually not necessary. 

In the Expert Consensus survey (Rush and Frances, 2000), respondents were asked to rate which classes of medication may be helpful for treating patients with severe and persistent physical aggression and those who destroyed property. The atypical antipsychotics were rated most highly, followed by anticonvulsant/ mood stabilizer. These were followed (with much lower priority) by antidepressants and beta-blockers. Among the atypical antipsychotics, risperidone was rated most highly, followed by olanzapine others had much lower ratings. Divalproex or valproic acid and carbamazepine were rated highest of the mood stabi-... 

In the Expert Consensus survey (Rush and Frances, 2000) the expert clinicians rated newer atypical antipsychotics highest for treatment of schizophrenic patients who are compliant with medication. Risperidone was rated highest of the atypicals, followed by olanzapine. In the case of patients with numerous failed trials with other antipsychotics, the experts voted for clozapine. For patients noncompliant with oral medication, respondents endorsed long-acting depot antipsychotics. Once again, these were impressions based on personal clinical experiences rather than hard empirical data. 

Several newer antipsychotic medications have been developed that seem different or atypical, compared with their predecessors. These agents include clozapine (Clozaril), risperidone (Risperdal), and several others listed in Tables 8-1 and 8-2. Although there is some debate about what exactly defines these drugs as atypical, the most distinguishing feature is that they have a much better side-effect profile, including a decreased risk of producing extrapyramidal (motor) side effects.17,45,57... 

Other classes of medications that may be used for pediatric insomnia include mood stabilizers/anticonvulsants (depakote), other classes of antidepressants (mir-tazapine), atypical antipsychotics (risperidone), and chloral hydrate, as well as herbal... 

Tardive or withdrawal dyskinesias, some transient but others irreversible, seen in 8%-51% of antipsychotic-treated children and adolescents, mandate caution regarding casual use of these drugs. Tardive dyskinesia has been documented in children and adolescents after as brief a period of treatment as 5 months and may appear even during periods of constant medication dose. Cases of tardive dyskinesia have been reported in youths treated with risperidone, indicating that atypical antipsychotics may also cause this serious adverse reaction. 

Until the advent of the atypical antipsychotics, conventional agents were widely used, although available placebo-controlled studies suggested that they were moderately effective at best. More recently, risperidone has been shown to have modest effects in patients with psychotic symptoms or behavioral disturbances associated with dementia. " It is recommended to begin with 0.25 mg daily and to titrate in 0.25- to 0.5-mg increments to 1 mg daily, which is usually considered the optimal dose. If response is inadequate, further titrating to a maximum of 2 mg daily may be necessary if the patient is tolerating the medication however, side effects, particularly extrapyramidal effects, somnolence, and orthostasis, increase with increased dose. 

Atypical or nontraditional antipsychotic medications have fewer movement symptoms than the typical antipsychotics. Examples of these medications include (see Table 7.3) clozapine (Clozaril), risperidone (Risperdal), sertindole (Serlect), olanzapine (Zyprexa) and quentiapine (Seroquel). These medications have gained popularity because they appear to have lower EPS proflles and they help individuals to think more clearly and follow directions better, to learn new facts and master new skills, and to interpret emotion more accurately (Lambert, 1998). 

When an antipsychotic is needed, we prefer using one of the newer atypical agents olanzapine, ziprasidone, risperidone, quetiapine, or aripiprazole. Each of these medications reliably reduces agitation and is well tolerated. In particular, they decrease the potential for acute dystonic reactions and tardive dyskinesia caused by the typical antipsychotics. Both ziprasidone and olanzapine are now available in an injectable form that is very rapidly acting and effective in this setting. 

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