Although currently available antidepressants increase monoamine levels soon after the start of treatment, therapeutic benefits are often delayed by several weeks and the majority of patients with ...major depressive disorder fail to achieve an adequate response to first- or second-line therapies targeting monoamines. The recent approval of the NMDA (N-methyl-d-aspartate) antagonist esketamine given intranasally for treatment-resistant depression has reinforced the need for agents with rapid onset with alternate mechanisms of action. Dextromethorphan/bupropion, an investigational medicine currently in development, is one such candidate.
Cariprazine is a new therapeutic agent recently approved for the treatment of both schizophrenia and manic or mixed episodes associated with bipolar disorder, and is under investigation for the ...treatment of both bipolar depression and major depressive disorder.
Parkinson's disease psychosis (PDP) is theoretically a serotonin-dopamine imbalance syndrome due to disruption of the normal balance between the serotonergic and dopaminergic neurotransmitter systems ...in key brain circuits.
Brexpiprazole is a new therapeutic agent that was recently approved for the treatment of schizophrenia and for the adjunctive treatment of major depressive disorder. Brexpiprazole has features that ...both overlap and contrast with a related molecule, aripiprazole, and these features are discussed here.
Pimavanserin, a novel agent approved for the treatment of Parkinson's disease psychosis, has potent actions as an antagonist/inverse agonist at serotonin 5HT2A receptors and less potent ...antagonist/inverse agonist actions at 5HT2C receptors.
In this paper, we will discuss the pharmacologic properties of antipsychotics, including those that are the same in structure and those that differentiate one from another. We will bring to you how ...differential pharmacologic properties can explain differential efficacy and differential tolerability. We will review how to use plasma drug levels and long-acting injectables to enhance compliance early in the illness, and to manage both forms of treatment resistance (pharmacokinetic and pharmacodynamic failures). Through inadequate pharmacokinetic processes (poor absorption, rapid metabolism, enzymatic polymorphisms, etc.), antipsychotic plasma levels do not reach sufficient concentration. Pharmacodynamic treatment failure (receptor binding and sensitivity, post-receptor effects, etc.) is the inability to provide a significant effect on psychotic symptoms despite therapeutic plasma levels. Long-Acting Injectable (LAI) antipsychotics employ technology that can provide a useful treatment tool in the armamentarium of a modern psychopharmacologist. The pharmacologic properties of antipsychotics differentiate one from another and can help explain differences in efficacy and tolerability. Utilizing plasma drug levels can enhance understanding of treatment failures and lead to specific patient management strategies for best outcomes. This kind of personalized approach to antipsychotic dosage would mean a big shift in the treatment of psychiatric patients.
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