Antipsychotics selection

The answer is b. (Hardman, pp 282—283J Central dopamine receptors are divided into Dt and D2 receptors. Antipsychotic activity is better correlated to blockade of D2 receptors. Haloperidol, a potent antipsychotic, selectively antagonizes at Dz receptors. Phenothiazine derivatives, such as chlorpromazine, fluphenazine, and promethazine, are not selective for D2 receptors. Bromocriptine, a selective D2 agonist, is useful in the treatment of parkinsonism and hyperprolactinemia. It produces fewer adverse reactions than do nonselective dopamine receptor agonists... 

Greater cantion regarding antipsychotic choice and use is necessary in the elderly, in patients with preexisting cardiac disease, and in patients taking dinretics or medications that may prolong the QTc interval. In patients older than 50 years of age, a pretreatment ECG is recommended, as are baseline sernm potassium and mag-nesinm levels. These factors shonld be considered in antipsychotic selection. ... 

Correlation between clinical effectiveness and receptor affinities, however, can be seen with other receptors in addition to the dopamine D2 receptor. These include other dopaminergic receptors, as well as noradrenergic and serotonergic receptors. For example, most antipsychotics also have high affinity for a -adrenoceptors and 5-HT2 receptors (225). Some antipsychotics have been shown to be selective for the adrenoceptor versus the a -adrenoceptor, for example, spiperone [749-02-0] (226) and risperidone (61) (221]... 

More interesting is the mechanism of action of atypical antipsychotics, particularly clo2apine (60). It is also probably the least selective antipsychotic used in the clinic, having high affinity for numerous receptors including 5-HT2, 5-HT, and dopamine D, D3) and receptors ... 

There is, however, a unique risk in the bipolar form that antidepressant treatment may trigger a switch into mania. This may occur either as the natural outcome of recovery from depression or as a pharmacological effect of the drug. Particular antidepressants (the selective serotonin reuptake inhibitors) seem less liable to induce the switch into mania than other antidepressants or electroconvulsive therapy. Treatment for mania consists initially of antipsychotic medication, for instance the widely used haloperidol, often combined with other less specific sedative medication such as the benzodiazepines (lorazepam intramuscularly or diazepam orally). The manic state will usually begin to subside within hours and this improvement develops further over the next 2 weeks. If the patient remains disturbed with manic symptoms, additional treatment with a mood stabilizer may help. 

Antipsychotics, bromocriptine, carbamazepine, chlorpropamide, cyclophosphamide, desmopressin, ecstasy, lamotrigine, monamine oxidase inhibitors, NSAIDs, oxcarbazepine, oxytocin, tricyclic antidepressants, selective serotonin reuptake inhibitors, vasopressin, vinblastine, and vincristine... 

List a reason why risperidone was selected as the next antipsychotic choice for AG. 

Tricyclic antidepressants Monoamine oxidase inhibitors Selective serotonin reuptake inhibitors Antipsychotics Phenothiazines Risperidone Lithium... 

What are the expected differences in side-effect profiles between ethnic groups, in particular with selective serotonic re-uptake inhibitors and atypical antipsychotics Can the morbidity of medication side effects be reduced, hence increasing treatment compliance and effectiveness ... 

Several diverse, potent, and selective GlyT-1 inhibitors have appeared in the literature and many are reported to be efficacious in animal psychosis models. Several of these have advanced into Phase I and Phase II clinical studies. Recent Phase II results from a double-blind, 320-patient study with the investigational GlyT-1 inhibitor RG1678 (33) [17] demonstrated that the compound improved negative symptoms and social functioning of stable patients currently on atypical antipsychotic therapy and was well tolerated at all doses tested [18]. 

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