Because of the importance of maintaining current knowledge of technological advances involving genetics, neuroscience, and their impact on psychopharmacology, we have created a new column for advanced practice psychiatric nurses.
This new column offers a question-and-answer forum that can help nurses maintain their knowledge of advances in prescribing and psychopharmacology, and implications for safe psychiatric care. Deborah Antai-Otong has a wealth of knowledge and expertise with prescriptive authority and as a psychotherapist. She currently manages the care of patients with various psychiatric disorders including mood disorders, schizophrenia, dual diagnosis, and anxiety disorders. She is the author of numerous refereed journal articles and book chapters that focus on psychopharmacology and is a guest lecturer at a local university on this topic. She is also the author of several books, including Psychiatric Nursing: Biological and Behavioral Concepts (Clifton Park, NY: Delmar & Thompson Learning, 2003) and Psychiatric Emergencies (Eau Claire, WI: PESI, 2001).
Historically, psychopharmacology has been an integral aspect of psychiatric care. The dawning of this century has generated an explosion of scientific studies that enhance positive patient responses to various psychopharmacological agents with fewer adverse side effects. Likewise, contemporary advances in brain imaging, genetics, neuroscience, neuroendocrinology, and molecular sciences provide a plethora of data that enhance the understanding of the complexity of pharmacological effects and specific cellular activities associated with mental disorders. These data offer opportunities for advanced practice psychiatric nurses to implement integrated models of mental health care using pharmacological and psychotherapeutic interventions.
The rapid technological advances of psychopharmacology require a thorough understanding of these complexities and their impact on safe medication and symptom management. Issues such as culture, ethnopharmacology, gender, age, cultural practices, stigma, and patient preferences also play significant roles in patient responses to pharmacological interventions. Finally, advances in molecular biology indicate a number of genetic polymorphisms exist in some enzyme systems (e.g., P450) and lead to alterations in drug metabolism.
Question: How do you manage medications for clients who take multiple medications for multiple problems?
Answer: It is difficult to predict drug-to-drug interactions that are inherent in multiple medical conditions; however, understanding complex processes is essential to the nurse who administers or prescribes medications. A brief review of pharmacokinetics and pharmacodynamics is crucial to understanding the patient's response to pharmacotherapy. Drug interactions are often characterized as either pharmacokinetic or pharmacodynamic.
* Pharmacokinetic interactions are those in which one drug alters the rate or degree of absorption, distribution, or elimination (metabolism or excretion) of another drug that may result in an increase or decrease in the concentration of the drug at the site of action. Key parameters include maximum serum concentration, half-life, total amount of drug excreted by the kidneys.
* Pharmacodynamic interactions are those in which one drug induces change in a patient's response to the drug without altering the drug's pharmacokinetic properties. For example, an increase of toxicity (doubled level) of lamotrigine (Lamictel) resulting from an interaction with valproic acid (Depakene).
Knowledge about the effect of various drugs on the cytochrome P450 enzymes is imperative, and enables the nurse to identify potentially serious or fatal drug-to-drug interactions. The metabolic conversion of drugs is normally enzymatic in nature. …