Essays on Pharmacokinetics

Multiple choice questions

Multiple Choice Questions

Increased erythropoietin production Increased heart rate Increased cardiac output Enhancement in oxygen extraction The answer for this question is b. increased heart rate. A reduction in tissue oxygenation as happens in anemia stimulates increased production of erythropoietin through a complex feedback mechanism. Increased production of erythropoietin enhances erythropoiesis in anemia. Increased extraction of oxygen in anemia is a compensatory mechanism that is mediated by an increase in 2, 3-diphosphoglycerate concentrations. Increased cardiac output is the main hemodynamic compensatory mechanism in anemia that aims to increase blood flow to the body organs. An increase in heart rate ...

Disease management constitutes an important area in the clinical research where drugs possess a significant position. The effect of drugs on various organ systems has been the area of much research interest which gradually made feasible the development of several classes of drugs. Drugs may have dual role of promoting and inhibiting the vital biochemical and molecular pathways that play influential role in the disease outcome.

Angiotensin converting enzyme (ACE) inhibitors are considered as anticongestive heart failure and antihypertensive agents. They have gained wide spread physician and patient satisfaction. The ACE inhibitors prevent the ...

Hilger RA, Richly H, Grubert M, Kredtke S, Thyssen D, Eberhardt W, et al,. Pharmacokinetics of Sorafenib in Patients with Renal Impairment Undergoing Hemodialysis. Int J Clin Pharmacol Ther.; 2009: 47(1); 61-64.

This study was focusing on the use of Sorafenib for the treatment of advanced renal cell carcinoma and hepatocellular carcinoma. It is a molecular inhibitor of a variety of tyrosine protein kinases and Raf kinases. Sorafenib is an oral inhibitor that inhibits the activity of threonine kinases. It has been approved in many countries including United States for the treatment of advanced renal cancer and primary liver ...

1942, Selman Maksman coined the word antibiotics. They are substances that are produced by microorganisms. They either slow down the growth of other bacteria or kill them right away. Examples include the beta-lactam antibiotics which consist of the penicilins. Others include the Carbapenems, the cephalosporins, the aminoglycosides, quinolones, sulfonamides and the oxazolidinones. Also, they could be classified as either bacteriostatic agents that slow down or inhibit the growth of bacteria or bactericidal agents which kill bacteria. Their discovery and use in medical science is of immense magnitude. They equally reduce the rate of mortality and morbidity of patients infected ...

Aim: To measure the partition coefficient values of sulphamidine and acetylsulphamidine present in water/octanol solution at different pH.

Abstract: After measuring the pH of the buffer solution, two lots of eight bottles were prepared. 5ml of drug and 5 ml of buffer solution were added to each bottle and shaken for 30 minutes. Absorbance was then of the solutions in the bottles was then determined. Introduction: Partition coefficient gives a measure of how a substance distributes in two different phase at equilibrium. Partition coefficient is utile in estimating the distribution of the drug within the body. There are two types ...

Abstract

The research paper discusses the origin and nature of methadone, including the historical aspect of its development and further commercial and scientific use. The paper also describes the pharmacology of methadone, including the route of administration of the drug, its metabolism and its mechanism of action. Next section of the paper explains the experience in medical use of methadone, as it`s a great alternative to the painkillers based on the opiates, it plays a major role in the therapy of maintaining and replacement and treating the withdrawals syndromes. The positive effects on the pregnant patients are also described here with a ...

Orphan Drug

Introduction The main purpose for the enactment of the U.S. Orphan Drug Act (ODA) of 1983 is to conduct a research on some of the rare diseases whose medical needs remain to be unresolved. The law has given incentives to various sponsors who have tried to develop therapies for some of the rare medical conditions that can affect at least 200,000 individuals on a yearly basis (Premiere Research 1). For this study, the objective is to create a regulatory strategy or path for Orphan Drug development, particularly on the oral iron chelator, one of the subsets of thalassemia or ...

Biosensors emerged as an important technology that has gained much attention in different fields of study. Biosensor is "a self-contained analytical device that combines the biological component with a physicochemical component for the detection of an analyte of biological importance." (Hasan et al. 2014). Perumal & Hashim (2013) defined it according to IUPAC recommendation of 1999, which states that a biosensor is, "an independently integrated receptor transducer device, which is capable of providing selective quantitative or semi-quantitative analytical information using a biological recognition element."The application of nanobiotechnology in the production of biosensors and various other applications is one of the most revolutionary trends ...

Analysis of NSAIDs non-selective take (Ibuprofen and Naproxen)

Health impact of many diseases leaves a potential consequence on the quality of life (QOL). The frequency at which such impact occurs could vary from one disease condition to the other. Affected individuals need to encounter physical and psychological distress. However, scientific advancements have made a progress in alleviating such problems. Especially, pharmaceutical science has become a reliable branch to cater the needs of people who suffer from illnesses. Understanding the efficacy and other properties of various drugs is important for the better therapeutic application of pharmacy. In such context, the present description deals with highlighting about Analysis of NSAID take by ...

MEDICINE

Systematic Clearance Extended Calculation Fraction Unbound (fu): 0.5 Clearance by active Secretion (CLsec):5.4/Lhr Fraction reabsorbed (FR): 0.2 Hepatic Extraction Ratio (Eh): 0.1 Calculating the (Vd): Volume of Distribution of drug on administration =Vd=Xo/Co Vd= Xo/Co =300mg/Anti-log1.26 Vd = Xo/Co = 300mg/18.2 ug/ml = 16.5lts Total Systematic Clearance, ClT = ClT=KeVd ClT = KeVd = 5.4/hr x 16.5 lts =0.299/60mins x 1000ml = (4933.5/60)ml/min = 82.23ml/min

Assumptions:

i) The Dose was administered intravenously ii) Co= Drug Plasma Concentration at zero time after it was administered

Therapeutic monitoring

Population pharmacokinetics is the study that focuses on ...

Systemic Clearance Extended Calculation

Data: Pharmacokinetic parameters: Fraction unbound (fu), 0.5; Clearance by active secretion (CLsec), 2L/h; Fraction reabsorbed (FR), 0.25; Hepatic Extraction Ratio (EH), 0.25. Q: Total Systemic Clearance (CLtotal) =? Formula: CLtotal = (F * D) / AUC (RMI Pharmacokinetics, 2014) Where, F = fraction of dose absorbed (mg), (1 – FR) * (1 – EH ) (RMI Pharmacokinetics, 2014) AUC = area under the curve (mg/L/h), (Δt /2) * Cf (Summit PK, 2014) D = single dose (mg), Q * AUC * F (RMI Pharmacokinetics, 2014)

Computation:

Step 1: Computation of F F = (1 – FR) * (1 - EH ) F = (1 - .25mg) * (1 - .25) = .75 * ...

BBB functions and physiology: The central nervous system (CNS) necessitates a highly controlled environment for its proper functioning. Blood brain barrier is the system which maintains the homeostasis of the CNS. It works by separating and shielding the brain from the constant changes in the nutrient and chemical composition of systemic blood. It protects the brain tissue from harmful chemicals that might be present in the blood. The key functions of the BBB are transport of nutrients from the blood to brain and metabolites in opposite direction to systemic circulation. Only a small number of molecules are allowed access through the ...

[Low flow anaesthesia with isoflurane in the dog]. This article in german compares the safety of high and low flow anesthesia in dogs preparing for surgery. Three groups of animals were divided into two low flow and one high flow groups. Vital signs were kept well controlled during the procedures. Notes the highest decrease in body temperature was in the high flow group, and a particularly cooled gas used for that group may have caused this. At least in the context of dogs, this article seems to treat the question of flow rate and core body temp. as a ...

Part ABriefly discuss the signalling process which occurs when salmeterol binds to its targetReceptor

The receptor to which salmeterol binds The drug salmeterol binds to the active sites of beta-2-adrenergic receptor . This is a category of G protein-coupled receptors. Beta-2-adrenergic receptors have specific actions in the body. They are responsible for the relaxation of smooth muscles relaxation of a non-pregnant uterus, dilation of arteries in the skeletal muscles, contraction of the sphincter muscles and anabolic processes in the skeletal muscle. The receptor has a three dimensional crystallographic structure. The receptors work by ensuring rapid and specific signaling. The receptors couple with Gs G protein, the result being the activation of adenylyl cyclase. The receptors have ...

Introduction

The information provided by pharmacokinetics is important in the discovery of new drugs and in screening drug candidates. It helps in drug research and can determine the concentration of a drug present in the body. The discovery of new medicines not only depends on pharmacological activity but on pharmacokinetic parameters as well. Pharmacokinetics includes absorption, distribution, metabolism and execration (ADME). Absorption is the absorbing of a drug in the blood stream. There are two types of absorption, passive and active. The physico-chemical properties are responsible for passive transportation while the active transportation determines the binding of a molecule to the target site. ...

Howard University

My name is Abdulfattah Yahya M Alhazmi. I am applying for your Graduate Program in Pharmaceutical Sciences because I am interested in specializing in Pharmacokinetics. I am impressed with the vision of your Department especially the recognition that as clinical therapeutic problems change, new research efforts need to be creative and flexible in order to successfully meet these new challenges. In fact, I have written a systematic review titled "Inappropriate use of proton pump inhibitors" in order to highlight my abilities in performing high quality research to improve clinical therapy. I agree with your department’s statement that innovation and ...

Lorazepam

Introduction Depression of the central nervous system (CNS) has been a vital technical know-how in the cure of anxiety, increase of sedation, decrease in tension, and curing of insomnia through enhancement of sleep. Similarly, depression of the CNS is believed to produce a continuum effect in the generation of anesthesia and loss of consciousness, which aid in alleviating anxiety (Aschenbrenner &Venable, 2009). In light with this, there are a variety of effects associated with the depression of the CNS, and they are largely attributed to the drugs used as a depressant. Dosage and the route of administration are the core determinants in ...

Pharmacogenomics alternatively referred to as pharmacogenetics in medical literature is a component of personalized medicine. It refers to the study of genetic polymorphisms that in one way or another influence individual response to drugs. Clinical observations on the effects of genetic polymorphism on the pharmacokinetics and pharmacodynamics of drugs were first documented back in the 1950s. Scientific knowledge on genetic variations is therefore the critical foundation on which pharamacogenomics is based. In specific, the knowledge of how variations in the genes responsible for encoding enzymes and proteins are the main pillars of pharamacogenetics (Belle, 2008). Enzymes play a vital role in ...