Traditional versus atypical antipsychotics antiemetic definition

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About 3 million Americans suffer from schizophrenia. Although this disease is not curable, there are many treatment options that suppress the symptoms. Doctors routinely recommend the use of antipsychotic drugs as the primary treatment. Over the years, two different categories of antipsychotic drugs have been developed (traditional and atypical antipsychotics). However, the question still remains of whether traditional or atypical antipsychotics should be prescribed to reduce the symptoms of this debilitating disease?

Schizophrenia comes from the Greek words meaning split and mind, but people with schizophrenia do not have split personalities. Rather, split mind refers to the fact that people with schizophrenia are split off from reality and can not distinguish what is real from what is not real.

Schizophrenia is a misregulation of information in the brain. There are three different hypotheses as to the etiology of schizophrenia. The first is that there are many different neurotransmitter pathways presumed to be involved in the biological basis of the disorder. The second is that genetics may play an important role and the third, is that the environment may trigger a possible genetic predisposition. It is most likely that a combination of the three trigger the onset of schizophrenia.

The symptoms of schizophrenia have been broken down into two categories, positive and negative. Positive symptoms include, hallucinations, delusions, disorganized speech, increased goal directed activity, and illogical thoughts. Negative symptoms include blunted affect, impaired emotional responsiveness, apathy, loss of motivation/interest, and social withdrawal.

Despite the fact that schizophrenia is not curable, there are treatment options that help suppress the symptoms. Psychological treatments, such as supportive psychotherapy and reality oriented; family therapies are often used. In addition, social interventions aimed at reducing relapses and facilitating reintegration into society have proven useful. The primary treatment option is usually the use of antipsychotic medications.

Antipsychotics are a group of drugs that are used to treat a handful of psychiatric disorders characterized by disturbed thought and behavior, most notably schizophrenia. Although they are not curative, they relieve some of the debilitating symptoms of this group of disorders (1). The precise mechanism of action that accounts for the effects of antipsychotic medications is still unknown. However, the dopamine hypothesis is the predominate theory used to explain the action of these drugs. Dopamine produces its effects by activating dopamine receptors on postsynaptic neurons. Many antipsychotics appear to act by blocking dopamine receptors in the brain.

There are two categories of antipsychotics, traditional antipsychotics and atypical antipsychotics. Traditional antipsychotics were first developed in the 1950’s and were used to treat psychosis, particularly schizophrenia. They are especially good at reducing the positive symptoms, but do not reduce the negative symptoms. Traditional antipsychotics are broken into two classifications: low-potency and high-potency. Common side effects of traditional antipsychotics include: dry mouth, tremors, weight gain, muscle tremors, and stiffness. In addition, traditional antipsychotics yield extrapyramidal side effects. These side effects include: motor disturbances, parkinsonian effects, akathesia, dystonia, akinesia, tardive dyskinesia, and neuroleptic malignant syndrome. Some of these side effects have been described to be worse than the actual symptoms of schizophrenia.

The first atypical antipsychotic, Clozapine was discovered in the 1950’s, but was not introduced clinically until the 1970’s. However, it quickly fell out of popularity due to drug induced agranulocytosis (loss of white blood cells that fight infection). During the 1990’s olanzapine, risperidone, and quetiapine were introduced into the market. Atypical antipsychotics treat both the positive and negative symptoms of schizophrenia. Side effects of atypical antipsychotics include: agranulocytosis, weight gain, and some extrapyramidal side effects. Atypical antipsychotics are considered to be the first line of treatment for schizophrenia and are gradually replacing traditional antipsychotics.

Are atypical antipsychotics always better than traditional antipsychotics? Some advantages atypical antipsychotics have over traditional antipsychotics are that there are fewer anticholinergic side effects, less parkinsonian and dystonia side effects, and they suppress the negative symptoms. They also have a lower propensity for causing extrapyramidal side effects. However, each atypical antipsychotic has a different chemical structure and therefore side effects vary from drug to drug. In addition, many atypical antipsychotics are compared to haloperidol (a traditional antipsychotic that yields numerous extrapyramidal side effects) and therefore it is not surprising that the atypical antipsychotics have an improved extrapyramidal side effect profile in comparison. Many atypical antipsychotics produce fewer side effects at lower doses, but once the dose is increased to maintain a therapeutic effect, the severity and number of side effects also increases. In a study done by John Geddes, Nick Freemantle, and Paul Bebbington, Atypical antipsychotics in the treatment of schizophrenia: Systematic overview and meta regression analysis, 12,649 patients in 52 randomized trials comparing atypical antipsychotics (amisulpride, clozapine, olanzapine, quetiapine, risperidone, and sertindole) with traditional antipsychotics (haloperidol and chlorpromazine). The researchers found that there is no clear evidence the atypical antipsychotics are more effective or are better tolerated than traditional antipsychotics. Traditional antipsychotics should usually be used in the initial treatment of an episode of schizophrenia unless the patient has previously not responded to these drugs or has unacceptable extrapyramidal side effects (2).

Even though traditional antipsychotics and atypical antipsychotics are both effective in treating some of the symptoms of schizophrenia, it seems like atypical antipsychotics are more effective because of their ability to suppress the negative and positive symptoms. Although they do contain some side effects, the severity of the side effects is less in atypical antipsychotics. Maybe a combination of traditional and atypical antipsychotics is the best way to treat schizophrenia.