As an advanced practice nurse assisting physicians in the diagnosis and treatment of disorders, it is important to not only understand the impact of disorders on the body, but also the impact of drug treatments on the body. The relationships between drugs and the body can be described by pharmacokinetics and pharmacodynamics.
Pharmacokinetics describes what the body does to the drug through absorption, distribution, metabolism, and excretion, whereas pharmacodynamics describes what the drug does to the body.
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When selecting drugs and determining dosages for patients, it is essential to consider individual patient factors that might impact the patient’s pharmacokinetic and pharmacodynamic processes. These patient factors include genetics, gender, ethnicity, age, behavior (i.e., diet, nutrition, smoking, alcohol, illicit drug abuse), and/or pathophysiological changes due to disease.
For this Discussion, you reflect on a case from your past clinical experiences and consider how a patient’s pharmacokinetic and pharmacodynamic processes may alter his or her response to a drug.
- Review the Resources for this module and consider the principles of pharmacokinetics and pharmacodynamics.
- Reflect on your experiences, observations, and/or clinical practices from the last 5 years and think about how pharmacokinetic and pharmacodynamic factors altered his or her anticipated response to a drug.
- Consider factors that might have influenced the patient’s pharmacokinetic and pharmacodynamic processes, such as genetics (including pharmacogenetics), gender, ethnicity, age, behavior, and/or possible pathophysiological changes due to disease.
- Think about a personalized plan of care based on these influencing factors and patient history in your case study.
By Day 3 of Week 1
Post a description of the patient case from your experiences, observations, and/or clinical practice from the last 5 years. Then, describe factors that might have influenced pharmacokinetic and pharmacodynamic processes of the patient you identified. Finally, explain details of the personalized plan of care that you would develop based on influencing factors and patient history in your case. Be specific and provide examples
Pharmacology is the study of the interactions between drugs and the body. The two broad divisions of pharmacokinetics refers to the movement of drugs through the body, whereas pharmacodynamics refers to the body’s biological response to drugs. Pharmacokinetics describes the drug’s exposure by characterizing absorption, distribution, bioavailability, metabolism, and excretion as a function of time, while pharmacodynamics describes drug response in terms of biochemical or molecular interactions (Arcangelo et al., 2017). The focus of this discussion will be in the process of warfarin in term of pharmacokinetics and pharmacodynamics of it in the body. Ms. J.J. ‘s Health issue: I was in charge of Ms. J. care couple years ago, a 85 year old African American women who was diagnosed with dementia cerebral infarction due to unspecified occlusion of cerebral artery, arthropathy, major depressive disorder, atrial fibrillation with a history of long-term use of anticoagulants, contracture of muscle, constipation, hypertension and GERD. She is currently on coumadin for the atrial fibrillation and the blood levels are monitoring every week in order to control the drugs therapeutic levels and avoid any adverse reactions. Pharmacodynamics versus pharmacokinetics of this anticoagulant: Many statistics from the stroke prevention in atrial fibrillation (SPAF) trial suggest that safety of anticoagulant in the elderly can be maximized through a careful monitoring and maintenance of the INR which is between 2 and 3. Ms. J’s therapeutic window for warfarin 2 to 3 which is the normal range for coumadin therapeutic level. Her weekly dosage is adjusted to her current blood levels. Bleeding is the most related complication of anticoagulant. Amy INR that increasing to 3.4 or 4.0 from Ms. J will result in nose bleeding, decreasing the coumadin or stop it for one or two days will be the only option (Horton & Bushwick, 1999). Factors influencing Ms. J’s drugs therapy: Multiple factors may affect the absorption of her medication. For example, the presence or the absence of flood in the stomach, blood flow to the area for absorption, and the dosage form of the drug. In Ms. J’s case, the most critical factor. Influencing her absorption of coumadin is gastric motility due to the history of constipation that she has, while a routine laxative dose and stools softens are administered daily for bowel movement. Patient-centered care plan for management of constipation: A non-pharmacologic care plan management can be introduced for the constipation in order to reduce the frequency and the quantity of laxative and stool. Softens doses that Ms. J is getting and ultimately gain a net decrease in gastrointestinal absorption of coumadin. Increasing a dietary fiber in her menu, encourage fluid and prune juice can have a significant impact on her bowel movement (Portalatin & Winstead, 2012). Portalatin, M., Winstead, N. (2012). Medical Management of Constipation. Clinic in Colon and Rectal Surgery. Doi: 10.1055/s-0032-1301754. Retrieved from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3348737/ Horton, J. D., Bushwick, B. M. (1999). Warfarin Therapy: Evolving Strategies in Anticoagulation American Family Physician. 59(3):635-646. Retrieved from https://www.aafp.org/afp/1999/0201/p635.html Arcangelo, V. P., Peterson, A. M., Wilburg, V., Reinhold, J. A. (2017). Pharmacotherapeutics for Advanced Practice: A Practical Approach. (4th Ed.). Wolters Kluwer Lippincott Williams &