Psychoses antipsychotics indicated

The causes for behavioural symptoms are often multiple. Sometimes the condition is caused by a drug which then of course should be withdrawn. When antipsychotic dugs are indicated for treatment of psychosis in Alzheimer s disease... 

The most common indications for antipsychotic drugs are the treatment of acute psychosis and the maintenance of remission of psychotic symptoms in patients with schizophrenia. More recently, the atypical antipsychotics have become part of the standard repertoire for the treatment of bipolar disorder, as discussed in Chapter 5. Antipsychotic drugs also ameliorate psychotic symptoms associated... 

The 2004 Practice Guideline for the Treatment of Patients With Schizophrenia recommends indefinite maintenance treatment for patients who have had at least two episodes of psychosis within 5 years or who have had multiple previous episodes (Lehman et al. 2004). Maintenance therapy should involve the lowest possible doses of antipsychotic drugs, and patients should be monitored closely for symptoms of relapse. If the patient is compliant with treatment, oral medications are usually sufficient. However, if the patient s treatment history suggests that the patient may not reliably take daily oral medication, a long-acting depot preparation may be indicated. 

Consequently, antipsychotic drugs all share a basic mechanism of action that involves dopamine receptor blockade. It is apparent, however, that they are not all equal in their ability to affect specific sub-types of dopamine receptors, and that their effectiveness and side effects are related to their affinity and preference for certain receptors. As indicated earlier, other neurotransmitters may also be involved in the pathogenesis of psychosis, and differences in specific antipsychotic medications may be related to their ability to directly or indirectly affect these other transmitters as well as block dopamine influence. Future studies will continue to clarify how current antipsychotics exert their beneficial effects and how new agents can be developed to be more selective in their effects on dopamine and other neurotransmitter pathways. 

Some of the antipsychotics are available as intramuscular injections for patients who are imable or unwilling to swallow tablets (as is common in psychosis or severe behavioural disturbance). Halo-peridol is most often used for these indications on psychiatric inpatient wards (chlorpromazine i.m. being restricted due to hypotension and skin nodule formation). Olanzapine may be given i.m. 

Indications Psychosis, manic-depressive disorders Category Antipsychotic, phenothiazine Muscarinic antagonist Half-life initial 2 hours terminal 30 hours Clinically important, potentially hazardous interactions with alcohol, antihistamines, arsenic, chlorpheniramine, dofetilide, epinephrine, evening primrose, guanethidine, mivacurium, quinolones, sparfloxacin... 

Thioridazine (50 to 100 mg p.o. t.i.d.) is indicated in psychosis. Thioridazine has potent anticholinergic properties and causes heavy sedation. However, it produces a very low incidence of extrapyramidal reactions such as akathisia, dystonia, parkinsonism, tardive dyskinesia, and neuroleptic malignant syndrome. Thioridazine is metabolized to mesoridazine, which is an active antipsychotic (see Table 19). 

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