Shared Flashcard Set

Details

Principles of Pharmacological Care
Pharmacokinetics, pharmacodynamics, drug interactions, etc
63
Pharmacology
Graduate
08/26/2009

Additional Pharmacology Flashcards

 


 

Cards

Term
Bioavailability
Definition
The fraction of drug that reaches systemic circulation after a particular route of administration
Term
Bioequivalence
Definition
The drugs (generic and parent) are considered equal to each other in containing same active ingredients, dosage form, and route. They must act the same way in the body. All other parts of the drug may be different (additives/lots) Ranges and tolerances vary Generic drugs are as good as the parent. Made to same standards as regular drugs.
Term
Chemical name
Definition
Describes the drug's chemical composition and molecular structure
Term
Bioavailability depends on route
Definition
IV=100% bioavailable Oral=affected by 1st pass, solubility, formulation, competition,
Term
Liver
Definition
Detoxifies, Makes fat soluble compounds more water soluble,
Term
Dosing pattern by route (dosing curve)
Definition
IV = Concentration starts high and decreases
Oral drugs = concentrations starts low and increases, peaks, plateaus, and metabolized off
(same curve for all drugs that are absorbed)
Term
Drug potency
Definition
Amount of drug you need to get a certain effect
Term
Factors that affect absorption
Definition
Route, Molecular nature of the drug, Food, Dosage formulation, status of the absorptive surface, Rate of blood flow, acidity of stomach, status of motility
Term
Routes of Administration
Definition
Enteral (GI), Parenteral, Topical (can have local or systemic effect)
Term
Passive Diffusion
Definition
The amount absorbed is related to the amount administered. particles travel along concentration gradient
Term
First Pass effect
Definition
A drug given via the oral route may be extensively metabolized by the liver before reaching the systemic circulation (high first-pass effect)
Term
Distributions
Definition
The transport of a drug in the body by the bloodstream to its site of action
Term
What factors affect distribution
Definition
Size of drug molecule
Polarity (large positively charged molecules cannot be absorbed ie aminoglycocides and must be delivered IV except neomycin tabs for c-diff or gent eye drops)
Water soluble vs. fat soluble
Blood flow
Capillary permeability (blood brain barrier)
Binding to proteins
Term
*Important concept r/t distribution
(hint, r/t protein binding)
Definition
Only "free" drug is pharmacologically active
Only free drugs can have an effect
Only free drugs can be metabolized
Term
Protein binding
Definition
drugs bound to proteins are not available nor are they able to be metabolized. Proteins are too big to leave the blood vessels and drugs bound to proteins will also not be able to leave the blood vessel
Term
*Displacement
Definition
One drug may out-compete the other drug or substance
Term
Axonal Conduction
Definition
Conduction of an action potential down the axon of the cell
• Drugs that act on axonal conduction are not very selective as they will affect conduction in all nerves they have access
• Local anesthetics are the only drugs that work by altering axonal conductions
Term
Synaptic transmission
Definition
Information is carried across the gap between the neuron and the postsynaptic cell
Drugs can elicit selective responses
Term
5 steps of synaptic transmission
Definition
1. transmitter synthesis 2. Transmitter storage 3. Transmitter release 4.
Term
What is the location and response to activation of the receptor, Nicotinic N? (peripheral cholinergic)
Definition
Location: All autonomic nervous system ganglia and the adrenal medulla

Response to activation: Stimulation of parasympathetic and sympathetic postganglionic nerves and release of epinephrine from the adrenal medulla
Term
What is the location and response to activation of the receptor, Nicotinic M (peripheral cholinergic)
Definition
Location: Neuromuscular junction

Response to activation: Contraction of skeletal muscle
Term
What is the location and response to activation of the receptor, Muscarinic (peripheral cholinergic)
Definition
Location: All parasympathetic target organs:

Eye: contraction of the ciliary muscle focuses the lens for near vision. Contraction of the iris sphincter muscle causes miosis

Heart: Decreased rate

Lung: Constriction of bronchi and promotion of secretions

Bladder: voiding

GI tract: Salvation, increased gastric secretions, increased intestinal tone and motility, and defecation

Sweat glands: sweating (ACt supply from sympathetic nervous system)

Sex organs: Erection

Blood vessels: Vasodilation (receptors not part of nervous system however)
Term
What is the location and response to activation of the receptor, Alpha 1 (peripheral adrenergic)
Definition
Location:

Eye: Contraction of the radial muscle of the iris causes mydraisis

Arterioles: Constriction

Veins: Constriction

Sex organs: Ejaculation

Bladder neck and prostatic capsule: Contraction
Term
What is the location and response to activation of the receptor, Alpha 2 (peripheral adrenergic)
Definition
Location: Presynaptic nerve terminals

Response to receptor activation: Inhibition of transmitter release
Term
What is the location and response to activation of the receptor, Beta 1 (peripheral adrenergic)
Definition
Location: Heart: Increased rate force of contraction, and increased AV conduction velocity

Kidney: Renin release
Term
What is the location and response to activation of the receptor, Beta 2 (peripheral adrenergic)
Definition
Arterioles (heart, lung, and skeletal muscle): Dilation

Bronchi: Dilation

Uterus: Relaxation

Liver: Glycogenolysis (breakdown of glycogen to glucose)

Skeletal muscle: Enhanced contraction, glycogenolysis
Term
What is the location and response to activation of the receptor, Dopamine receptors in the PNS
Definition
Location: Vasculature of the kidney

Activation: Dilates renal blood vessels
Term
Receptor specificity of adrenergic transmitters
Definition
Epinephrine: can activate all alpha and beta receptors but not dopamine

Norepinephrine: Can activate alpha 1, alpha 2, and beta 1, but not beta 2 or dopamone

Dopamine: Can activate alpha 1, beta 1, and dopamine receptors
Term
Seven regulatory functions of the parsympathetic nervous system
Definition
➢ Slows heart ➢ Increases GI secretions ➢ Constrict bronchiole smooth muscle ➢ Emptying bladder ➢ Emptying bowel ➢ Constriction of the pupil ➢ Focusing the eyes for near vision
Term
Principle functions of the sympathetic nervous system
Definition
➢ Regulation of the cardiovascular system
➢ Regulation of body temperature
➢ Implementation of the “fight-or-flight” reaction
Term
Six categories of cholinergic drugs
Definition
1. Muscarinic agonists: Bethanechol
2. Muscarinic antagonists: atropine
3. Ganglionic stimulating agents: Nicotine (Nicotinic N)
4. Ganglionic blocking agents: Trimethaphan
5. Neuromuscular blocking agents: d-tubocurarine and succinylcholine (block ACh @ Nicotinic M)
6. Cholinesterase inhibitors: Neostigmine, physostigmine (indirectly activate all cholinergic receptors)
Term
Chemical name
Definition
Describes the drug's chemical composition and molecular structure
Term
Generic name
Definition
Name given by the US Adopted Name Council
Term
Trade Name
Definition
The drug has a registered trademak; use of the name is restricted by the drug's patent owner
Term
Drug
Definition
Any chemical that affects the physiologic processes of a living organism (not a food)
Term
Pharmacology
Definition
The study or science of drugs
Term
Pharmacotherapeutics
Definition
The use of drugs and the clinical indications for drugs to prevent and treat diseases
Term
Absorption
Definition
The process drugs of entering the body
Term
pharmacokinetics
Definition
Drug movement includes Absorption, distribution, metabolism, and excretion
Term
Pharmacodynamics
Definition
Drug effect
The study of what the drug does to the body
Term
Volume of drug distribution (Vd)
Definition
how much plasma you would need to have if the drug was present and accounted for in plasma. (Normally 4-5L) Gives an estimate of how the drug is being distributed. A volume of less than 0.071 L/Kg means that the drug is staying in circulation. A volume greater than 0.071 L/Kg means that the drug has left the circulatory system (or that you would have needed to have much more volume to account for the amount of drug measured) Lithium has small Vd and loves to stay in blood and could be dialized out. Pheno has a huge Vd and is out in tissues and cannot be dialized out.
Term
Metabolism (biotransformation)
Definition
The biologic transformation of a drug into a more water soluble (polar) compound; Usually into an inactive metabolite, or a less potent metabolite (however may be more potent metabolite ie prodrug)
CYP 450 enzymes are responsible for most of drug metabolism
Codeine is transformed into morphine by enzymes in the liver. Some people do not have the enzyme that metabolizes codeine and do not experience pain relief
Term
Prodrug
Definition
Cytoxin (chemo drug) is completely inactive when given and is made into the active form by enzymes in the liver.
Toxicity of drugs can be affected by metabolism ie Demerol is metabolized into an agent that causes seizures
Term
Phases of drug metabolism
Definition
Phase I: conversion to less lipophilic compound involves the cytochrome P-450 system Phase II: Conjugation
Term
Factors that decrease metabolism
Definition
Cardiovascular dysfunction, renal insufficiency, hepatic disease, genetics, drug therapy, toxins
Term
Excretion/Clearance
Definition
The elimination of drugs from the body
Term
Factors affecting excretion
Definition
Age, gender, body weight and composition, protein binding, kidneys (GFR, tubular reabosorption, tubular secretion), Pulmonary, Bowel
Term
Crockcroft-Gault Equation to Predict GFR
Definition
Clcr (cc/min) = [140-age] x IBW/72 x Scr X [0.85 if female]
Creatinine comes from lean muscle. Lost over time
greater than 80 cc/min normal
Less than 50 cc/min impaired renal function
Take general body weight unless pt is third spacing to significant degree
Term
Half-life
Definition
The time it takes for one half of the original amount of a drug in the body to be removed
Measures the rate drugs are removed
This is a kinetics term, and does not refer necessarily to the duration of the therapeutic effect
Takes approximately 5 half-lives to clear drug
Term
Steady State
Definition
The amount of drug administered is equal to the amount of drug eliminated within one dosing interval resulting in a plateau or constant serum drug level
Term
Loading dose
Definition
Use of a loading dose helps one achieve desired therapeutic effect sooner. It does not alter the time required to achieve steady-state
Term
Linear (First-Order) Pharmacokinetics
Definition
Half-life remains constant no matter how high the concentration
Amount of metabolism changes with concentration
Term
Non-Linear Pharmacokinetics (Zero-order)
Definition
Fixed amount metabolized per Unit time
Half-life changes with concentration
Term
Michaelis-Menten Kinetics
Definition
Follows linear kinetics until enzymes become saturated
Term
Question: Drug X = renal toxic in patients with impaired renal function, given 100mg, if you get 50mg in renal impairment, med has 0 bioavailability. Will this drug cause toxic effect?
Definition
No. Drug is not bioavailable. Must be available to cause toxic effects
Term
Pharmacokinetics help clinician determine a drugs:
Definition
Onset (time it takes for drug to elicit a therapeutic response), Peak (the time it takes for a drug to reach its maximum therapeutic response), Duration (the time a drug concentration is sufficient to elicit a therapeutic response)
Term
Pharmacodynamics
Action vs. Effect
Definition
The study of what the drug does to the body
Action is how the drug works (enhancing or inhibiting)
Effect is consequence of drug action on body
Term
Drug receptors
Definition
Term
Grapefruit juice
Definition
Liver-like enzymes (CYP) in intestinal tract that like to chew on grapefruit juice (substrate) and are not available to chew on drugs that would normally be broken down thus making more drug available to be absorbed and metabolized.
Term
metabolite (NB)
Definition
may account for the drugs toxicity, duration of action, side effects etc.
Term
Therapeutic effect
Definition
Desired clinical effect
Term
Side effect
Definition
Action that occurs at therapeutic dose (due to pharmacologic actions of the drug)
May be predictable
May be used to produce a desired therapeutic effect (benadryl = drowsiness)
May decrease over time
Term
Adverse drug response
Definition
an unexpected or unintended response to a therapeutic dose of a drug
Supporting users have an ad free experience!