What is drug redistribution?
The movement of a substance from an area of high regional blood flow to an area of medium or low regional blood flow. This phenomenon may determine the duration of action of a drug.
How redistribution can terminate a drug action?
If the site of action of the drug was in one of the highly perfused organs, redistribution results in termination of the drug action. The greater the lipid solubility of the drug, the faster its redistribution will be.
What are the factors that affect distribution of a medication?
Drug distribution is affected by many factors, including plasma or tissue protein binding, body weight, body composition, and body fluid spaces (8). Of these, total body weight, muscle mass, and fat composition are the major determinants of drug distribution, and women may differ from men in both of these factors.
What is an example of drug distribution?
Drug distribution refers to the movement of a drug to and from the blood and various tissues of the body (for example, fat, muscle, and brain tissue) and the relative proportions of drug in the tissues.
How is a drug distributed in the various body compartments?
The extent of drug distribution into tissues depends on the degree of plasma protein and tissue binding. In the bloodstream, drugs are transported partly in solution as free (unbound) drug and partly reversibly bound to blood components (eg, plasma proteins, blood cells).
What does it mean when a drug is excreted unchanged?
If an active drug is metabolized mainly to inactive compounds, renal function will not greatly affect elimination of the parent compound. However, if the drug or an active metabolite is excreted unchanged via the kidneys, changes in renal function (i.e. chronic renal failure) will influence its elimination.
What determine the degree of movement of a drug between body compartments?
Movement of drug between different compartments (distribution/redistribution) is determined by the concentration gradient between compartments and the inter-compartmental clearance.
How is drug distribution determined?
The apparent volume of distribution (Vd) for a drug is defined as the hypothetical fluid volume through which the drug is dispersed. It is calculated by dividing the total amount of drug given by the concentration of drug in plasma (Table 45.1,Eq.
How does body size affect drug distribution?
The main factors that affect the tissue distribution of drugs are body composition, regional blood flow and the affinity of the drug for plasma proteins and/or tissue components. Obese people have larger absolute lean body masses as well as fat masses than non-obese individuals of the same age, gender and height.
What is the importance of drug distribution?
Understanding drug distribution is important in establishing: The amount of drug available to the target organ to produce action. The amount of drug distribution to nontarget organs that could potentially result in an adverse drug reaction. The loading dose of drugs.
Why is thiopental used as an anesthetic?
Anesthesia for Cesarean Delivery Thiopental 4 to 6 mg/kg provides a rapid and reliable induction of anesthesia. As a negative inotrope and vasodilator, thiopental can cause decreased cardiac output and blood pressure,253 which may result in significant hypotension in hypovolemic patients.
What is drug redistribution in nursing pharmacology?
Drug redistribution from its initial site of concentration, drug-plasma protein binding and factors influencing renal clearance are presented. Pharmacokinetics for Nursing Pharmacology: Drug Redistribution Nursing Pharmacology Chapter 2: General Principles: Pharmacokinetics Redistribution Termination of drug effects: Usually by:
What are the different types of drugs accepted for redistribution?
Types of drugs accepted for redistribution (e.g. over-the-counter drugs, condition-specific drugs). Eligible donors, recipients and patients. Protocols for transferring and repackaging donated drugs. Maximum pharmacy dispensing fees. Agency oversight.
What is postmortem drug redistribution?
Key concepts in postmortem drug redistribution Postmortem redistribution (PMR) refers to the changes that occur in drug concentrations after death. It involves the redistribution of drugs into blood from solid organs such as the lungs, liver, and myocardium.
Who can donate prescription drugs to the drug repository?
Who can donate: Any person, including but not limited to a prescription drug manufacturer or health care facility, may donate prescription drugs to the prescription drug repository program.