The first line psychiatric treatment for schizophrenia is antipsychotic medication. These can reduce the positive symptoms of psychosis. Most antipsychotics take around 7–14 days to have their main effect. Currently available antipsychotics fail however to significantly ameliorate the negative symptoms, and the improvements on cognition may be attributed to the practice effect.
|Risperidone (trade name Risperdal) is a common atypical antipsychotic medication |
The newer atypical antipsychotic drugs are usually preferred for initial treatment over the older typical antipsychotic, although they are expensive and are more likely to induce weight gain and obesity-related diseases. In 2008, results from a major randomized trial sponsored by the US National Institute of Mental Health (Clinical Antipsychotic Trials of Intervention Effectiveness, or CATIE) found that a representative first-generation antipsychotic, perphenazine, was as effective as and more cost-effective than several newer drugs (olanzapine, perphenazine, quetiapine, risperidone, or ziprasidone) taken for up to 18 months. The atypical antipsychotic which patients were willing to continue for the longest, olanzapine, was associated with considerable weight gain and risk of metabolic syndrome. Clozapine was most effective for people with a poor response to other drugs, but it had troublesome side effects. Because the trial excluded patients with tardive dyskinesia, its relevance to these people is unclear.
The two classes of antipsychotics are generally thought equally effective for the treatment of the positive symptoms. Some researchers have suggested that the atypicals offer additional benefit for the negative symptoms and cognitive deficits associated with schizophrenia, although the clinical significance of these effects has yet to be established.
Because of their reportedly lower risk of side effects that affect mobility, atypical antipsychotics have been first-line treatment for early-onset schizophrenia for many years before certain drugs in this class were approved by the Food and Drug Administration for use in children and teenagers with schizophrenia. This advantage comes at the cost of an increased risk of metabolic syndrome and obesity, which is of concern in the context of long-term use begun at an early age. Especially in the case of children and teenagers who have schizophrenia, medication should be used in combination with individual therapy and family-based interventions.
Recent reviews have refuted the claim that atypical antipsychotics have fewer extrapyramidal side effects than typical antipsychotics, especially when the latter are used in low doses or when low potency antipsychotics are chosen.
Prolactin elevations have been reported in women with schizophrenia taking atypical antipsychotics. It remains unclear whether the newer antipsychotics reduce the chances of developing neuroleptic malignant syndrome, a rare but serious and potentially fatal neurological disorder most often caused by an adverse reaction to neuroleptic or antipsychotic drugs.
Response of symptoms to medication is variable: treatment-resistant schizophrenia is a term used for the failure of symptoms to respond satisfactorily to at least two different antipsychotics. Patients in this category may be prescribed clozapine, a medication of superior effectiveness but several potentially lethal side effects including agranulocytosis and myocarditis. Clozapine may have the additional benefit of reducing propensity for substance abuse in schizophrenic patients. For other patients who are unwilling or unable to take medication regularly, long-acting depot preparations of antipsychotics may be given every two weeks to achieve control. The United States and Australia are two countries with laws allowing the forced administration of this type of medication on those who refuse but are otherwise stable and living in the community. At least one study suggested that in the longer-term some individuals may do better not taking antipsychotics.
A 2003 review of four randomized controlled trials of EPA (an omega-3 fatty acid) vs. placebo as adjunctive treatment for schizophrenia found that two of the trials detected a significant improvement on positive and negative symptoms, and suggested that EPA may be an effective adjunct to antipsychotics. The most recent meta-analysis (2006) failed however to find a significant effect. A 2007 review found that studies of omega-3 fatty acids in schizophrenia, despite being mostly of high quality, have produced inconsistent results and small effect sizes of doubtful clinical significance.
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