Schedule of Drugs
What is a schedule I drugs abuse potential/dependence? Examples? Rules?
High abuse potential/severe dependence
Heroin, LSD
No acceptable use, research only
Define: Pharmacokinetics
Importance?
Study of drug movement throughout the body
-Determine drug concentrations at sites of action
-Need to ensure drug concentrations are high enough to elicit desired response
-Informs the dosing, route, and schedule for individual
Define Pharmacodynamics
What drugs do and how!
Biochemical and physical effects of drugs and mechanism of action
Mechanisms and effects of medications
Factors that impact of drugs safety?
How its stored, how expensive it is, sharing medications, medication error, how its administered, allergies, adverse reaction/effects
Define: drug
Chemicals that produce effects by interacting with other chemicals
Medications bind to specific receptors
What is a schedule V abuse potential/dependence? Examples? Rules?
Limited abuse, low dependence
Antidiarrheal drugs, small amount of opioid in a medication mixture
Many OTC
What is a half-life? How many half-lives until drug is approx. 94% gone?
Time required to eliminate 50% of the total amount of drug in body
Drug almost completely eliminated in approximately four half-lives
Define: potency
Amount of concentration of the drug we give to get an effect
Less concentration = more potent
More concentration = less potent
Example:
Fentanyl is more potent vs Tylenol
What is a medication error? Examples? How to prevent it?
Any preventable event that may cause or lead to inappropriate use or harm to the patient
Examples: communication mistakes, name confusion (SALA,LASA), Human Factors- stocking errors, distraction, fatigue/stress, miscalculation
Prevent by medication reconciliation
Define: receptors
Special chemical sites that most drugs interact with to produce an effect
Usually found in the nucleus or cytoplasm of cell
Recognize hydrophobic ligands (e.g., steroids)
What is a schedule II abuse potential/dependence? Examples? Rules?
High abuse potential/severe dependence
Amphetamines, some opioids
Electronic or tamper-resistant rx, no refills
What route of administration bypasses absorption?
Advantages? Disadvantages?
IV (Intravenous)- no barrier, no absorption required, instantaneous and complete
Advantages: rapid onset, control over blood levels, permits use of large volumes, drugs that are irritants may be better managedDefine: affinity
What does increased affinity equal?
The strength of the attraction between the drug and its receptor
Increased affinity = increased potency
What year was the controlled substances act?
1970
Simple vs Modified Occupancy Theory
Simple: Potency and Maximum Efficacy
Modified: Affinity and Intrinsic Activity
-Increased affinity= increased potency
-Increased intrinsic activity = increased intense receptor activation = maximum efficacy
What is a schedule III abuse potential/dependence? Examples? Rules?
Moderate abuse potential/moderate dependence liability
Some opioids, some stimulants, anabolic steroids
Written or telephone rx every 6 months, refills allowed
The chemical changes that occur before the drug reaches the systemic are called...
First Pass Metabolism
All orally administered medications must FIRST PASS through the liver before reaching systemic circulation
Define Agonist
Define Antagonist
What is a partial agonist?
Agonist: mimic action of endogenous ligand
Has affinity and intrinsic activity
Antagonist: block action of endogenous ligand (effect depends on concentration of endogenous ligant)
Has affinity but NO intrinsic activity
Partial agonist (agonist-antagonist): mimic and block
Has affinity and moderate intrinsic activity
Can function as an antagonist in the presence of a full agonist
What is a controlled substance? Who regulates controlled substances?
Drugs that have the potential to be abused
The drug enforcement administration (DEA)Record keeping isrequired by regulation of all inventory and transactions
*Most providers need a second person to dispose of a medication*
Define Therapeutic Range? How is it measured?
AKA Therapeutic Window: range of blood level in the body where the drug has a therapeutic effect. Associated with safe medication levels.
How much drug is in the blood:
-Need blood tests to mark if we are in the range
-Toxic level ABOVE the TR
-Ineffective levels below the TR
What is a schedule IV abuse potential/dependence? Examples? Rules?
Low abuse potential, limited dependence
Tranquilizers, weak opioids
Same as Schedule III - written or telephone rx every 6 mon, refills allowed
Kidney
1) Glomerular Filtration- fluids and molecules move through capillary pores into tubular urine
2) Passive tubular reabsorption - must be lipid soluble to pass
3) Active tubular secretion - transport systems in tubule pump drugs from blood into tubular urine
What is the Dose Response Relationship? Broken down into...?
Relationship between the size of the administered dose and intensity of the response intended
Relationship is gradedWhy is the nursing role important?
RN is the last line of defense against errors
RN is the last person with opportunity to make an error
RN is the person whose actions are not ROUTINELY checked by others
-Right patient, right medication, right route, right time, right dose (5 rights)
-Safe, selectivity, predictability (characteristics of ideal drug)
Define Therapeutic Index? High vs low?
A concept that is frequently used:
Measure of a drugs safety - ratio of LD50: ED50
We determine maximum tolerated dose in humans rather than lethal dose in animals
Large/high TI: relatively safe
Small/low TI: relatively unsafe