General Principles of Pharmacology Flashcards
What are the steps involved in the marketing of drugs?
Preclinical testing, clinical testing phases I, II & III, and Phase IV or post marketing surveillance
What does a drug need to be approved for marketing by the Food and Drug Administration (FDA)?
Drug must be shown by studies to be “safe and effective”
What is “indications?”
Conditions for the drugs use
What is “unlabeled” uses for drugs?
Therapeutic utility for different purposes or in populations other than those described in the package insert
Which group of people are considered “therapeutic orphans?”
Pregnant women, women of child bearing age, infants, and children
What is Bioavailability?
is the percentage of the dose of the drug administered by any route reaches the systemic circulation
What is bioequivalence?
equivalent release of the same drug substance from 2 or more drug products or formulations
Are drugs with the same same active ingredient bioequivalent?
No; to be bioequivalent when they produce AUC, Cmax and Tmax values that are neither clinically nor statistically different
What is Pharmacology?
The total knowledge of drugs including history, chemistry, source, biochemical & physical effects, pharmacodynamics (what the drug does to the body), pharmacokinetics (what the body does to the drug), therapeutics, site of action, interactions, distinctive features, etc.
What is a Drug?
any substance which, when introduced into the body, produces a physiological change, a biological change, a decrease in population of resident or invading microorganisms, or a decrease in abnormal tissue development
What are Orphan drugs?
development of drugs for treatment of diseases affecting fewer than 200,000 patients in the US, or for research using commonly available (nonpatentable) chemicals for treatment of specific diseases
What is Clinical pharmacology?
The study of the effect of drugs in man
What is Pharmacotherapeutics?
deals with use of drugs in prevention & treatment of disease, usually to alleviate symptoms or, sometimes, to alter the course of the disease. The emphasis is on the disease and the treatment thereof
What is therapeutic index and how is it calculated?
The relative toxicity of a drug this is the ratio of the dose capable of killing 50% of animals (LD50) over that required to achieve a beneficial effect in 50% of the animals (ED50)
What constitutes a “small therapeutic index?”
little difference between the therapeutic dose and the dose that causes toxicity
What is Tolerance?
is hyporeactivity that occurs from chronic exposure to a drug
What is CROSS TOLERANCE?
tolerance between drugs within a class; or between drugs of different classes that produce similar pharmacologic effects
What is enzyme induction?
stimulate production of drug-metabolizing enzymes resulting in increased rate of metabolism and usually decreased blood level of the drug
What is down regulation?
is a decrease in the number or sensitivity of receptor sites after continued dosing
What is up regulation?
the body may either increase the number of receptors or increase the sensitivity of receptors
What is Idiosyncrasy?
describes an unusual effect of a drug
What is Side effect?
describes any action of the drug other than the desired (therapeutic) effect
What is Adverse Effect?
is any noxious, unintended, and undesired effect that occurs at normal drug doses
According to the Controlled Substances Act, addictive substances are categorized into?
schedules (I through V)`
What drugs are Schedule I?
(Written C-i): Addictive substances with no approved use (e.g., heroin)
What drugs are Schedule II?
C-ii: Highly addictive substances (e.g., morphine; amphetamine). Prescriptions must be written in ink or typed or submitted using electronic prescribing procedures and cannot be refilled. A DEA rule in 2007 allows a prescriber to write multiple prescriptions on the same day for the same patient and same drug to be filled sequentially for up a 90 day supply. (I did not see this but I assume C-ii prescriptions are limited to a 30 day supply.)
What drugs are Schedule III and Schedule IV?
C-iii & C-iv: Less addictive; may be prescribed orally and may be refilled up to 5 times in 6 months (e.g., aspirin with codeine C-iii; diazepam C-iv)
What drugs are Schedule V?
C-v: Low addictive potential. Texas law requires a prescription for C-v drugs so essentially, in Texas, there is no difference in prescribing or how schedules iii, iv & v are handled. See Lehne p. 434 for more comprehensive description of the various DEA schedules.
What is Pharmacokinetics?
is the quantitative study of the absorption, distribution, metabolism and excretion of drugs and their metabolites. In simple terms, pharmacokinetics (often simply called “kinetics”) is what the body does to the drug.
What factors affect Plasma membranes?
molecular size and shape, solubility at the site of absorption, the degree of differences in pH across the membrane, the electrochemical gradient for the lipid form of the drug, degree of ionization, vascularity of the tissue, and relative solubility of ionized and nonionized forms
What substances cannot penetrate Plasma membranes?
Polar molecules (e.g., soluble in water) and ions cannot penetrate membranes and require transport systems.