Principles of Pharmacology COPY Flashcards
Pharmocology
Study of how various substances interact with or alter the function of living organisms
Opium Expolsuion Act
In 1909 was created to stop import of opium
Food, Drug, and Cosmetic Act
In 1938 the US FDA was given enforcement authority for rules requiring that new drugs were safe and pure
FDA
Responsible for approving new drugs
Controlled Substances Act
Classifies certain medications into five categories with potential of abuse and addiction
Schedule 1
High Abuse potential:
May not be prescribed, dispensed, used or administered for medical use and has no recognized medical purpose
Ex: heroin, marijuana, lsd
Schedule 2
High Abuse Potential:
Has a medical purpose but is required t be under constant lock and key, records kept and proper storage
Ex: fentanyl, Ritalin, cocaine
Schedule 3
Lower Potential Abuse:
Must remain under lock and key with records kept and proper storage
Ex: hydrocodone, codeine, ketamine
Schedule 4
Lower Potential Abuse:
S/a 2-5
Ex: diazepam, lorazepam, midazolam
Schedule 5
Lower Potential Abuse:
S/a 2-5
Ex: narcotic cough drops
Synthetic
Made in a labratory
Sources of Medication exampls
Plant: atropine, aspirin, digoxin, morphine
Animal: heparin, antivenom, insulin
Microorganism: streptiknoase, antibiotics
Minerals: iron, magnesium, Sulfate, lithium
Medication Name
Given three different names
Chemical: very long name (sodium bicarbonate)
Generic Name: usually contain stem at the end of the name to link it to other medications lam, pine, lol, lal
Brand Name: Lasix, Tamiflu, Lopressor makes it easier to remember drug generic name
Pharmacodynamics
When a medication alters a function or process in the body
Pharmokinetics
The action of the body on a medication
Receptor Site with Medication
Either
1: ion passages may open or close
2: bio mechanical messenger becomes activated initiating other reactions in cell
3: normal cell function prevented
4: normal or abnormal function of cell begins
Exogenous
From outside of the body
Agonist Medications
Initiate or alter a cellular activity by attaching to receptor sites, prompting a cell response
Ex: opiates
Antagonist Medications
Prevent endogenous or exogenous agonist chemicals from reaching cell receptor sites and initiating or altering a particular cellularactivity
Ex: nalaxone
Affinity
Ability of a medication to bind with a particular receptor site
Medication Concentration and Affinity
Determine how many receptor sites are bound by that medication
-only certain amount of receptors and all receptors can be taken up
Minimum Concentration
Certain minimum of medication must be present to activate cellular activity
Threshold Level
When initiation or alteration of cellular activity begins
Potency
The concentration of a medication required to intpitiate a cellular response
-when potency is low, a higher concentration is needed
Efficacy
Ability to initiate or alter cellular activity in a therapeutic or desired manner
One-Response Curve
Relationship of medication dose or concentration and efficacy
-once threshold is reached increasing dose increases efficacy until maximum effect range is reached then increasing dose has no effect
Competitive Antagonists
Temporarily bind with cellular receptor sites, displacing agonist chemicals
-until wasted naturally by kidneys
Noncompetetive Antagonists
Premnently bind with receptor sites and prevent activation by agonist chemicals
-effects continue until new receptor sites are made or until new cells are made
-Ex:
Ketamine NCA of Glutamate of the CNS
Aspirin NCA of Cyclooxygenase causing antiplatelet effects
Partial Agonist
Attach to cellular receptor sites but do not cause as much change as other agonists
-effectively lower efficacy of other agonists
Chelating Agents
Bind with heavy metals such as lead, mercury, and arsenic in the body nod creating a compound that can be eliminated
Diuretic
Draws excess water from certain body tissues including the brain and the eyes while enhancing excretion of urine by the kidneys
Medication Distribution
Distribute into either water, lipids or fat, and protein
Water-Soluble medication
Higher weight based dosing must be administered to infants because they have a higher percentage of water compared to adults and elederly
Ex: digoxin
Fat and Lipid medication
Require higher weight based doses in elederly people because of a higher body fat percentage and increased fat distribution
Ex: benzodiazepines
Paradoxical Reaction
Clinical effects opposite from desired effect
Formula Ideal Body Weight
In KG
Men: 50 + (2.3 times patients height in inches over 5 feet)
Women: 45.5 + (2.3 times patients height in inches over 5 feet)
Temperature
Hyper and hypothermia can effect body absorption of medication
- fever causes tachycardia that increases hepatic blood flow increasing initial metabolism of drugs in the liver and decreasing amount of drug delivered to circulation
- hypothermia impairs acls Medications. Atropine and lidocaine generally seen as ineffective.
Genetic Factors
Primary Pulmonary Hypertension: may have acute decompensation when vasopressor medications are used
Aspirin: may precipitate hemolysis in patients with bleeding disorders
Sickle Cell: medications such as lasix (diuretics) or alpha 1 agonists may fatally worsen condition
Pregnancy
Hematocrit (percentage of RBC’s in plasma decrease due to increase in plasma)
Categories Desgined:
A- no risk to fetus
B- may have been effect in rates but none shown in women
C- are adverse effects on pregnancy. Drugs given only if benefit outweighs risk
D- fetal risk apparent.
X- fetal abnormalities. Contraindicated in pregnant women.
Placebo Effect
Fake medication given and still seen to cause change
Therapeutic (desired) Response
One that achieves a desired result by medication administration
Cumulative Action
Using multiple medications to achieve desired result
Adverse Medical Effects
untoward effects
Clinical changes, caused by medication, that are not desired and cause some degree of harm or discomfort to the patient
Ex: hypoglycemia after insulin administration, bradycardia after beta blocker, and allergic reaction
Stevens Johnsons Syndrome
Severe possible fatal medication administration reaction that mimics a burn
Idiosyncratic Reaction
Abnormal susceptibility to a medication due to genetic factors, dysfunction of metabolic enzyme, and peculiar to patient
Median Lethal Dose
LD50: weight based dose that caused death in 50% of animals tested
Median Toxic Dose
TD50: 50% of animals tested had toxic effect at or above weight based dose
Median Effect Dose
ED50: does not harm and achieves desired effect
Therapeutic Index
Relationship between ED and LD or TD
-If a large gap between lethal and effective it is relatively safe. If not, must be used very carefully
Medication Sensitivity
Adverse reaction not desired such as hives or allergic reaction
Tolerance
When a medication is constantly taken and causes the patient to have a decrease in efficacy