January 10th, 2018
Pharmacotherapeutic treatment for schizophrenia – new approaches to develop schizophrenia medications
New approaches for developing schizophrenia medications target glutamatergic neurons due to their suggested positive effect on negative symptoms and cognitive deficit that arise in schizophrenia (Tiihonen & Wahlbeck 2012). Examples of such drugs are D-cycloserine and GSK729327, whose trials were completed in 2005 and 2010 respectively, and Ampakine, whose trial was terminated in 2007 through a sponsor’s request (Clinicaltrials.gov 2012). A review of studies that carried out an intervention comprising a combination therapy of such glutamatergic drugs and other antipsychotics did not find significant evidence to recommend the use of glutamatergic agents in clinical practice (Tiihonen & Wahlbeck 2012).
In Australia, a trial sponsored by The Afred, is investigating the efficacy of Raloxifene, an oestrogen, in treatment of schizophrenia in women (ClinicalTrials.gov 2012). Other clinical trials being conducted in Australia are aimed at elucidating potential benefits of various antipsychotic enhancements (e.g. Quetiapine fumarate, and paliperidone palmitate) with regard to safety, tolerability and increased duration of action (ClinicalTrials.gov 2012).
Schizophrenia is a debilitating mental illness whose victims experience disruptions in cognitive, affect and behavioural functions. This paper evaluates the pharmacotherapeutic approaches for managing schizophrenia. Although, an absolute cure for the ailment is yet to be discovered, antipsychotic medications have been used successively to achieve symptom remission. Such antipsychotic drugs are thought to work principally by blocking D2-receptors, with the adverse effects associated with D2-receptor blockade leading to the development of atypical (second-generation) antipsychotics that exhibit D2/5HT affinity thus reducing the extrapyramidal side effects of typical antipsychotics. Antipsychotics exhibit drug interactions with such drugs as enzyme inducers and other drugs with which they compete for metabolic enzymes. Their contraindications relate to individual hypersensitivity and presence of disease conditions that heighten development of adverse effects of antipsychotics. New approaches to schizophrenia medication include medications targeting glutamate receptors and those seeking to reduce adverse effects of existing antipsychotics.
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