Reply Posts 1
Respond to a minimum of two peers on two separate days. Your responses should be in a well-developed paragraph (300-350 words) to each peer. Integrating an evidence-based resource that is different than the one you used for the initial post.
Your responses to each peer’s chosen drug categories should include one evidence-based article from the Regis College Library that connects culture, genomics, pharmacogenomics, or a particular age group (infant or pregnancy, for example.)
Respectfully agree and disagree with your peers’ responses and explain your reasoning by including your rationales in your explanation.
In your initial post, please select two classifications of drugs from the following list and explain the factors that may influence the pharmacokinetics and pharmacodynamics processes of these agents.
List of Drug Categories
· Selective Serotonin Inhibitors
· Fluoroquinolones
· Beta-Adrenergic Antagonists
· Antilipidemics
· Corticosteriods
· ACE Inhibitors
MY peer’s Initial post
In order to effectively treat a patient, it is important to understand the pharmacokinetics and pharmacodynamics of medications to meet a desirable outcome. However, there are certain factors to be considered that may affect different patient populations. The impact of medications such as Fluoroquinolones and ACE inhibitors on organ systems may be beneficial to some patients while other factors need to be considered to avoid negative effects.
Broad spectrum antibiotics, like Fluoroquinolones, are bactericidal to repair infectious DNA in organisms effected by gram negative, staphylococcus, enterococcus and streptococcus bacteria (Woo & Robinson, 2020). Despite the beneficial effects of fluoroquinolones, certain factors need to be considered that influence its pharmacokinetics and pharmacodynamics. Some factors include renal impairment in patients such as the elderly, those with kidney or liver transplants or those taking steroids for an extended amount of time (Woo & Robinson, 2020). These factors are important to consider in order to avoid toxicity and subsequent unfavorable events as the metabolism and excretion of fluoroquinolones are primarily via the renal and hepatic system (Woo& Robinson, 2020). Lengthening the dosing interval in patients with impaired renal function is also an important consideration when prescribing fluoroquinolones (Hoo, Liew & Kwa, 2017). It has also been found in a large cohort study that fluoroquinolone use was correlated with increased risk of tendon rupture (Merel & Paauw, 2017).
The pharmacokinetics and pharmacodynamics of ACE Inhibitors (ACEIs) lower blood pressure by acting on the renin-angiotensin-aldosterone system (Woo & Robinson, 2020). However, the action in ACE inhibitors also affect the elderly and those with renal impairment (Woo & Robinson, 2020). Due to its effect on the kinin-kallikrein-bradykinin system, ACE inhibitors facilitate the breakdown of bradykinin, therefore promoting vasodilation (Woo & Robinson, 2020). As a result, the effect of vasodilation prevents perfusion maintenance within the kidneys, potentiating ischemic or worsening renal failure (Woo & Robinson, 2020). The kidney is also the primary organ of excretion with the exception of a few different ACEIs (Woo & Robinson, 2020). With renal impairment, delayed excretion of ACEIs can significantly prolong the drugs half-life (Woo & Robinson, 2020). ACE inhibitors also increase the probability of adverse effects in the elderly due to physiological decline in renal and musculoskeletal function (Mukhtar & Jackson, 2015).
Understanding the pharmacokinetics and pharmacodynamics of medications is important in order to safely prescribe. While fluoroquinolones and ACE inhibitors can provide effective treatment for some patients, certain factors that influence the pharmacodynamics and pharmacokinetics can create undesirable effects. Factors such as the elderly and those with renal impairment can significantly influence how these medications effect the organ systems they target as well as metabolism and excretion.
References
Hoo, G. S.R., Liew, Y. X., & Kwa, A. L.H. (2017). Optimization of antimicrobial dosing based on pharmacokinetic and pharmacodynamic principles. Indian Journal of Medical Microbiology, 35(3), 340–346. doi.org/10.4103/ijmm.IJMM_17_278
Merel, S. E., & Paauw, D. S. (2017). Common drug side effects and drug-drug interactions in elderly adults in primary care. Journal of the American Geriatrics Society, 65(7), 1578– 1585. doi.org/10.1111/jgs.14870
Mukhtar, O., & Jackson, S. H. D. (2015). Drug therapies in older adults (part 2). Clinical Medicine, 15(2), 155–159. doi.org/10.7861/clinmedicine.15-2-155
Woo, T.M., & Robinson, M.V. (2020). Pharmacotherapeutics for advanced practice nurse prescribers. Philadelphia, PA: F.A. Davis
Reply Posts 2
Respond to a minimum of two peers on two separate days. Your responses should be in a well-developed paragraph (300-350 words) to each peer. Integrating an evidence-based resource that is different than the one you used for the initial post.
Your responses to each peer’s chosen drug categories should include one evidence-based article from the Regis College Library that connects culture, genomics, pharmacogenomics, or a particular age group (infant or pregnancy, for example.)
Respectfully agree and disagree with your peers’ responses and explain your reasoning by including your rationales in your explanation.
In your initial post, please select two classifications of drugs from the following list and explain the factors that may influence the pharmacokinetics and pharmacodynamics processes of these agents.
List of Drug Categories
· Selective Serotonin Inhibitors
· Fluoroquinolones
· Beta-Adrenergic Antagonists
· Antilipidemics
· Corticosteriods
· ACE Inhibitors
MY peer’s Initial post
Pharmacodynamics: Fluoroquinolones are bactericidal through interference with enzymes required for the synthesis and repair of bacterial DNA. They have been known for their extensive gram negative activity, some activity against gram-positive organisms, and varying activity against mycobacterium species. Due to mutations to the quinolone binding region and permeability of organisms, resistance to Fluoroquinoones has been increasing and should be reserved for use when alternatives may be more hazardous (Woo, 2020, pp 735). Pharmacokinetics: All drugs in this class are well absorbed orally and have similar concentrations when administered intravenously. Food may have a small effect on absorption although ciprofloxacin may have decreased absorption when given with dairy. The route of elimination does vary with each fluroquinolones; some have renal excretion with little metabolism while others have greater metabolism and then some have both. Few are excreted through feces. Renal impairments will have effects on half life of this drug.
Antibiotic stewardshipt is the effort to measure and improve how antibiotics are being prescribed by clinicians and used by patients (CDC, 2020). There has been more and more evidence to show that many antibiotics and antimicrobials are becoming less efficacious due to increase resistance and overuse. Resistance of Fluonoquinolones have been documented in E.coli, pseudomonas, enterococcus, and gonorrhea. A study conducted by Yang et. Al. indicated that resistant rates of all gram negative bacterial were significantly correlated with fluonoquinolone consumption in the hospital setting. While there were limitations to this study, evidence of resistance has been shown in many other settings. Therefore the use of this class of antibiotics should be used with caution.
Pharmacodynamics: Beta-adrenergic antagonists (Blockers) have their highest concentration of receptors in the heart but also can be found in the respiratory system and eyes. Beta receptors in the heart are mainly beta1 receptors, blockade of these receptors can decrease HR, contractility velocity and slow conduction. Together this can reduce angina, decreased cardiac rhythm disturabances, decrease blood pressure and reduce reflex orthostatic tachycardia. The blockade of beta1 receptors in the renal system reduces the release of renin which reduces blood pressure. Beta2 receptors throughout the body, in the lungs blockade of these receptors may lead to increased airway resistance. In the eye, beta blockers may reduce the intraocular pressure. Pharmacokinetics: Beta blockers are well absorbed when given orally. They are distributed in the body tissue and can have CNS penetration. Beta blockers are extensively metabolized in the liver and eliminated through bile and feces. Metabolism also has effects on half life of some of these medications and should be given with care for those with renal impairment because some of these medications can be excreted unchanged in the urine (Wo, 2016, pp 154-156).
Betablockers have been used for treatment of cardiac disorders such as heart failure and other disorders including essential tremors, migraine headache prophylaxis and hyperthyroidism. When prescribing these medications understanding the selectivity for beta1 and Beta 2 receptor sites should be taken into consideration with each patient’s condition. There is some debate as to whether or not beta blockers are the most efficacious in treating different cardiovascular disorders. A study conducted by Ziff et all (2020) suggest that while beta-blockers may be useful in resistant hypertension or those with cardiovascular comorbidities, the overall clinical effect depends on the clinical situation.
References
Ping,Y., Yunbo, C., Saiping, J.,Ping, S., Xiaoyang, L., and Yonghong, X. (2020) Association between the rate of fluoroquinolones-resistant gram-negative bacteria and antibiotic consumption from China based on 145 tertiary hospitals data in 2014. BMC Infectious Diseases (2020) 20:269 https://doi.org/10.1186/s12879-020-04981-0
Woo, T. M., & Robinson, M. V. (2016). Pharmacotherapeutics for advanced practice nurse prescribers. 4th edition, Philadelphia, PA: F.A. Davis Company.
Ziff, O.J., Samra, M., Howard, J.P., Bromage, D.I., Ruschitzka, F., Francis, D.P., Kotecha, D., (2020) Darrel P. Francis3 and Dipak Kotecha Beta-blocker efficacy across different cardiovascular indications: an umbrella review and meta-analytic assessment. BMC Medicine 18:103
https://doi.org/10.1186/s12916-020-01564-3