General Principles Flashcards
Absorption
A drug is moved from site of administration to body fluids (1st step in pharmacokinetics)
Adverse reaction
Undesirable drug effect
Allergic reaction
Immediate hypersensitive reaction by the immune system, usually presents as itching, hives, swelling, and difficulty breathing
Anaphylactic shock
Sudden, severe hypersensitivity reaction with symptoms that progress rapidly and may result in death if not treated
Angioedema
Localized wheals or swelling in subcutaneous tissues or mucous membranes which may be caused by an allergic response, aka angioneurotic edema
Controlled substances
Drugs that have the potential for abuse and dependency, both physical and psychological, most carefully monitored, prescriptions for these monitored by the DEA (agencies dispensing controlled substances must count them every 8-12 hours
Cumulative drug effect
When the body is unable to metabolize and excrete one dose of a drug before the next is given
Complementary/ alternative medicine (CAM)
Group of diverse medical practices or products not presently part of conventional medicine
Distribution
Drug moves form circulation to body tissue or target site
Drug idiosyncrasy
Any unusual or abnormal response that differs form the response normally expected to a specific drug and dosage
Drug tolerance
Decreased response to a drug, requiring an increase in dosage to achieve desired effect
Excretion
Elimination of drug from the body
First pass effect
Action by high an oral drug is absorbed and carried directly through the liver, where it is inactivated by enzymes before it enters the general bloodstream
Half life
Time it takes for body to eliminate half the drug
Herbal medicine
Type of complimentary/alternative therapy that uses plants or herbs to treat various disorders
Hypersensitivity
Undesirable reaction produced by a normal immune system
Metabolism
Drug is changed to a from that can be excreted
Metabolite
Inactive form of the original drug
Nonprescription Drugs
Drugs designed by the FDA to be safe and obtainable without a prescription aka OTC, reading directions is important, OTC doesn’t mean no risks
Pharmaceutic
Pertaining to the phase during which a drug dissolved in the body, liquid or injection drugs absorb the fastest, and solid forms of a drug go through this in the GI tract
Pharmacodynamics
Study of the drug mechanisms that produce biochemical or physiologic changes in the body
Pharmacokinetics
Study of drug transit or activity after administration, includes ADME,
Physical dependency
Habitual use of a drug, where negative physical withdrawal symptoms result from abrupt discontinuation
Prescription drugs
Drugs the federal government has designated as potentially harmful unless their use is supervised by a licensed healthcare provider such as nurse practitioner, physician, or dentist, may cause different reactions in different people
Psychological dependency
Compulsion or craving to use a substance to obtain a pleasurable experience
Receptor
A reactive site on the surface of a cell, when a drug binds to and interacts with the receptor, a pharmacologic response occurs
Risk evaluation and mitigation strategies (REMS)
FDA program designed to monitor drugs that have a high risk to benefit ratio, outlines specific educational requirements of healthcare providers,
Tetratogen
Drug or substance that causes abnormal development if the fetus, leading to deformities
Toxic
Poisonous or harmful
Chemical name
Describes molecular structure of drug, usually chemical component of drug
Generic name
Official name, name given to the drug that can be made or marketed by any company and is nonproprietary, given by FDA and found in the National Formulary and US Pharmacopeia
3 categories FDA assigns
Prescription, no prescription, controlled substance
Controlled substances act
Divided Drugs into 5 schedules
Drug development
Pre-FDA Phase: in vitro testing in animal and human cells, then studies in live animals
FDA phase: clinical (human) testing, phase 1= 20-100 healthy volunteers to see what drug does on healthy tissue, phase 2= drug is given to people with the disease, phase 3= drug given to a large number of people in medical research centers, then a NDA is submitted and the FDA either approves or denies it, if accepted, there is still post-marketing surveillance
orphan drug program
passed to encourage development and marketing if products for rare diseases, provides incentives such as research grants, protocol assistance by FDA, and tax credits
Accelerated programs
used as a means to make products more accessible faster for those with life threatening illnesses, essentially makes drugs available on the market before a final approval
How can absorption be accomplished? (Active Transport)
cellular energy is used to move the drug from an area of low concentration to an area of high concentration
How can absorption be accomplished? (passive transport)
no cellular energy is used as the drug moves from a low concentration to a high concentration area (small molecules diffuse across cell membrane
How can absorption be accomplished? (pinocytosis)
cells engulf the drug particle (cell forms a vesicle to transport the drug to the inner cell)
what influences the rate of absorption
route of administration, solubility, specific conditions in body tissues
during distribution, a drug can only produce a therapeutic effect if it is…
free. Drugs bound to protein in the bloodstream are pharmacologically inactive, and can only produce therapeutic effect when the proteins release the drug into tissues
where are drugs distributed the fastest
organs with the largest blood supply, (ex. heart, liver and kidneys) slowest in internal organs, skin and muscle
what types of drugs cross the cell membrane the easiest
lipid soluble, and water soluble cross the cell membrane the hardest
where are most drugs metabolized
liver, but kidneys, lungs, plasma, and intestinal mucosa also aid in metabolism of drugs
onset of action
time between administration and onset of its therapeutic effects
peak concentration
when absorption rate equals elimination rate
duration of action
length of time the drug produces a therapeutic effect
how does a drug exert its actin
2 main ways: alteration in cellular function, and alteration in cellular environment
alteration in cellular function
increase or decrease certain physiologic functions, like heart rate, blood pressure or urine output
receptor mediated drug action
when a drug molecule selectively joins with a receptor site
agonist
drug that binds with the receptor and stimulates it to provide a therapeutic response
antagonist
joins with a receptor bu doesn’t stimulate it, therapeutic effect come form blocking the receptors actions
alteration in cellular environment
include changes in osmotic pressure, lubrication, absorption, or the conditions in the surface of the cell membrane
pharmacogenomics
study of how peoples responses to medications are different because of individual genetic variation
when does allergy to a drug begin to occur
when more than one dose of the drug has been given
why does a drug allergy occur
body treats drug as a foreign substance
which allergic reactions are the most serious
typically ones that occur the fastest
allergic symptoms
itching, skin rashes, hives (urticaria), difficulty breathing, wheezing, cyanosis (sudden loss of consciousness), and swelling of the eyes, lips, or tongue
treatment goal of anaphylactic shock
raise blood pressure, improve breathing, restore cardiac function, and treat other symptoms as they occur (can inject epinepherine in the upper arm or thigh)
when is cumulative drug effect most common
in patients with kidney or liver disease
additive drug reaction
combined effect of each drug is equal to the sum of each drug given alone
synergistic drug effect
drugs produce an effect that is greater than their individual effects
antagonistic reaction
when when one drug interacts with another so that it neutralizes the effects of one of the drugs
factors influencing drug response
age (children and elderly require smaller doses), weight (doses may need to be increased if the patient is overweight or vice versa), sex (women may require smaller doses), diseases, routes of administration (oral requires a higher dose than IV)
herbal preparations
not necessarily safe because they have less testing
