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Pharm 250 > Module 1 > Flashcards

Module 1 Flashcards

1
Q

History of Pharmacology

  • who is pharm used by
  • chemists isolated substances when and how
  • Effects of drugs were studied how
  • Who were the earliest subjects
A
  • Used by every culture, dating back to antiquity
  • isolated pharm substances from natural substances in 1800
  • tested on animals
  • Early tests on themselves (the reseachers)
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2
Q

Canadian History

  • Louis Hebert is considered what, born where, and came to Canada when
  • What did he do
  • The people who helped him were indigenous to where
A
  • First apothecary born in Paris and moved to Quebec city in 1617
  • looked after pioneers and made drugs shown to him by Mi’kmaq
  • Indigenous to maritime provinces and Gaspé peninsula of Quebec
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3
Q

Pharmacology Now

  • Drugs are made where
  • Tested for how long
  • Understanding has what
  • focus is on what 2 (RI)
A
  • made in labs
  • tested over short times
  • Understanding has increased of how drugs produce their effects
  • focus on reliving suffering and improving quality of life
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4
Q

Conncection to Pharmacology

  • The practice of using products to relieve suffering has been recorded where
  • Pharm is intimately connected to what and is a key what
  • The greater understanding of medicine does what
A
  • Recorded throughout history by virtually every culture
  • connected to nursing practice and is Key intervention in relieving and preventing human suffering
  • More you understand meds the safer the pt
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5
Q
  • What is pharmacology

- it includes (4) HWAH

A

Study of medicines

  • how drugs are given
  • where they go
  • response produced
  • how its eliminated from body
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6
Q

Four factors of complexity

  1. L
  2. C
  3. I
  4. D
A
  1. Large volume of drugs
    - nomenclature can confuse communications between professions
  2. Each drug (within the class) has its own characteristics
    - Applications
    - interactions
    - side effects
    - action
  3. More than one indication
    - Overlapping map of knowledge
    - Cant diagnose by looking at med
  4. Give different responses depending on factors
    - age, sex, body mass, health status, genetics
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7
Q

Pharmacotherapeutics

Pharmacotherapy is the administration of drugs for either: (2) PT

It practices what kinds of medicine

Describe it

A

Administration for

  • prevention of disease
  • treatment of suffering

Practices Evidence - based medicine (EBM)

-Makes decisions according to well designed and conducted research

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8
Q

Three kinds of therapeutic agents DBN

A
  1. Drugs
    - Prescription
    - Over the counter
  2. Biologics
  3. Natural health products
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9
Q

What is a drug

What is a medication

Made where

A

A drug is a chemical agent that produces a biological response

Meds are medically therapeutic drugs

Made in labs

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10
Q

Biologics

  • Made with?
  • Derived from?
  • Examples
A
  • Medications made using living organisms (yeast, bacteria)
  • Complex large molecules derived from living things such as yeast and bacteria

Examples:

  • Hormones (insulin)
  • Monoclonal antibodies
  • Natural blood products
  • Interferon
  • Vaccines
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11
Q

Natural Health Products

  • examples
  • How are they different from modern drugs
  • any effect?
A
  • vitamins, minerals, herbal remedies, homeopathic meds, traditions meds, probiotics supplements (amino acids, fatty acids, protein)
  • Similar actions to modern drugs, regulated differently
  • Can have clinically significant effects and side effects
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12
Q

Prescription Drugs

Advantages 3 and 2 disadvantages

A

Advantages

  • Examines client and orders specific drug (personal)
  • Amount and frequency controlled
  • instructions on use, side effects identified and monitored

Disadvantages

  • Require prescription
  • An Appointment
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13
Q

Over the counter Drugs

Advantages 2 and 3 disadvantages

A

Advantages

  • No appointment
  • Less expensive

Disadvantage

  • Can choose wrong drug
  • May not know reactions
  • Bad treatment = worse health
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14
Q

Canadian Drug Regulations

  • What is the purpose
  • when did the standard start
  • what do some contain
A
  • Purpose is to protect Canadian public
  • Prior to the 19th century there were few standards
  • Some drugs contain hazardous levels of dangerous and/or addictive substances
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15
Q

Governance structure
(Top to bottom)
3 parts

A
  1. Food and drugs Act & Regulations
  2. Health Canada
  3. Health Products & Food Branch
    - Therapeutic products directorate
    - Biologics & genetic therapies directorate
    - Natural and Non-prescription Health Products Directorate
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16
Q

The Health Products and Food Branch

  • Part of?
  • Responsible for
  • Regulates
A
  • Part of Health Canada
  • Responsible for ensuring health products and food are safe and of high quality
  • Regulates the use of therapeutic products through directorates
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17
Q

Therapeutic Products Directorate (Health Products & Food Branch)

  • Authorizes what
  • Products must be proven to who
A
  • Authorizes marketing of a pharmaceutical drug (both prescription and over-the-counter*) or medical device
  • Products must be sufficiently scientifically proven (through clinical trials) to the Food and Drugs Act and Regulations
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18
Q

Biologics Genetic Therapies Directorate (Health Products & Food Branch)

  • Regulates
  • Examples of Biologics
  • Examples of radiopharmaceuticals
A
  • Regulates biologic drugs and radiopharmaceuticals
  • Examples of biologics: blood products, vaccines, tissues, organ and gene therapy products
  • Examples of radiopharmaceuticals: radioactive iodine for hyperthyroidism
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19
Q

Natural and Non-prescription Health Products Directorate (Health Products & Food Branch)

  • Regulates?
  • Conduct a review of what
  • Also setup regulations for?
A
  • Regulates the sale and use of natural health products (NHPs)
  • Conduct a review of the safety and appropriate use of each product before it can be authorized for sale
  • Also set up regulations for manufacturing within Canada or importation for sale in Canada
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20
Q

Prescription Drug Approval Process: New Drugs

6 step process PCCNHH

A
  1. Pre-Clinical Studies
    - 3 to 5 years
    - Test with cells of different species of animals
    - Initial info on potential safety and effectiveness
  2. Clinical Trial Application
    - Submits detailed info on pre-clinical studies to health Canada
    - Committee review info and authorize distribution
  3. Clinical Trials
    Phase 1 (20-100 healthy human volunteers in study)
    -dosage is determined
    -How drug is absorbed, distribution, metabolized and eliminated (ADME/ Pharmacokinetics) assessed

Phase 2 (100-300 volunteers who have disease)

  • Dosage
  • Side effects

Phase 3 (1000-3000 volunteers who have disease)

  • Double blind study (placebo or conventional treatment)
  • Clinical investigators assess results
  1. New drug submission
    - Health Canada evaluates drugs safety, efficacy, quality
  2. Health Canada issues permits to market drug product
    -Issues notice of compliance (NOC)
    -Issues drug identification number (DIN)
    [Then released into market]
  3. Health Canada monitors drug effectiveness and concerns post-marketing
    - includes health professional adverse drug reaction reporting
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21
Q

Adverse Drug Reaction Reporting

Minimum info needed (4) PDNC
And helpful info

A
  1. Patient information – demographics but not name
  2. Description of the adverse event
  3. Name of the health product – when in doubt, report!
  4. Contact information for yourself

Other helpful info: dates of use of product (start & stop), dates of reaction, lab tests, other health products used

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22
Q

Patent

  • What is a period of exclusivity
  • What is the intention
  • how long is the protection
  • registered when
  • What happens when it ends
  • Once the periods ends what happens
A
  • A period of exclusivity = where that pharmaceutical company only determines the price of the medication
  • Intention of patents is for company to recover high costs of research and development of product (trials)
  • Provides 20 years of patent protection; the actual length of exclusivity is ~ 7-9 years in Canada due to regulatory hurdles
  • Must be registered any time before the New Drug Submission step(step 4) – each individual drug may be different depending upon legal advice
  • Once that period of exclusivity ends, competing companies (generic companies) market the generic equivalent drug for less money, and consumer savings are considerable
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23
Q

Approval Process for Generics(Prescription and OTC)

  • How long compared to standard process
  • Must Prove what
  • What is bioequivalent (2 parts) AB
  • No need for clinical trials if
A

An abbreviated new drug submission

-Generic companies must prove their product is bioequivalent

  • Bioequivalent = the rate and extent to which the active ingredient is
    a) absorbed from a drug product, and
    b) becomes available at the site of drug action to produce its effect

*no need for clinical trials if proved bioequivalent

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24
Q

Generic Products

  • Can be safely used instead of
  • cautious when
A

-the generic equivalent may be safely substituted for the trade name drug (HCP opinion)

Cautious when:

  • critical, acute care drugs
  • those with a narrow therapeutic window/range
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25
Q

What is Therapeutic Classification

-Examples

A

Therapeutic Classification – organizing drugs according to their therapeutic usefulness in treating a particular disease

Examples:
anti-inflammatories – reduce inflammation
anti-convulsants – reduce seizures
immunosuppressants – suppresses immune system

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26
Q

What is pharmacological classification

  • examples
  • Addresses what
A

Pharmacological Classification – organizing drugs according to the way a drug works at a molecular level, tissue and body system level

Example:
calcium channel blocker – blocks calcium channels α-agonist – stimulates α-receptors
proton pump inhibitor – blocks proton pumps

Addresses a drug’s mechanism of action

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27
Q

What is a mechanism of action

A

= HOW a drug produces its effect on the body

Does it block a receptor (like a β-blockers)?
Does it inhibit something (like an ACE-inhibitors)?
Does it stimulate a receptor (like an α-agonist)?
What action does it create (like a vasodilator)?

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28
Q

Nomenclature
What is each

Chemical Name

  • Gives info on
  • Usage?

Generic Name
-Remains what

Brand/Trade
-Sometimes can what

A

Chemical name: a direct description of the chemical structure

  • Gives information about it’s chemical makeup
  • Use is limited – sodium chloride (NaCl), calcium carbonate (CaCO3)
  • 2-[4-(2-methylpropyl)phenyl]propanoic acid

Generic name: the unique name given to a chemical structure that somewhat describes it’s structure

  • Remains the same across languages (few exceptions)
  • Ibuprofen

Brand/Trade name: the marketed name given to a drug, usually short and easy to remember [HAVE THE R]
-Sometimes can sound-alike; differences between countries
-Champix® vs. Chantix®; Losec® vs. Lasix®
-Advil®
Motrin®

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29
Q

Safest to use what kind of name when referring to meds

-Reduces what and encourages what

A

Generic

  • reduces errors
  • efficient communication between disciplines and across borders
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30
Q

What happens when Patents expire

What must a generic company prove
-What can they not change and change

A

-When patents expire, any company can then manufacture that drug and charge less money for it (we call these generic companies)

A generic company must prove bioequivalence before their product can be sold

  • A generic company cannot change the active ingredient
  • It can change non-medicinal ingredients such as fillers and excipients (lactose, colours)
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31
Q

Controlled Substance are what and regulated how

A

Controlled substance = any drug in whose manufacture, possession, or use is regulated by the government

-Well regulated

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32
Q

Drug Scheduling (federal)

  • Regulated by 3
  • What does federal regulations do
  • Govern who
  • Do provinces have power
A

Food and Drug Act and Regulations – any drug requiring a prescription
Controlled Drugs and Substances Act
Narcotic Control Regulations

  • Control the import, production, export, distribution, and possession of narcotics and controlled substances
  • Govern manufacturers, pharmacies, hospitals and healthcare professionals – require proper security, detailed inventory records
  • Individual provinces cannot change the scheduling of any drug identified as a narcotic or controlled substance
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33
Q

Drug Scheduling (Provincial)
-Each prov and territory decides what
What are the 4 schedules

A

Each province and territory decides where to schedule each individual drug (except controlled substances and narcotics – always Schedule I)

Schedule 1 = prescription
Schedule 2 = without prescription, must be behind counter (ensure pharmacist interaction)
Schedule 3 = No prescription, sold in pharmacy (guarantee access to pharmacist)
Unscheduled = Anywhere

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34
Q

Pharmacokinetics is what

what is ADME

A

The study of how a drug moves in the body

Absorption
Distribution
Metabolism
Excretion

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35
Q

Pharmacokinetics: Nurse’s Role
The care a nurse provides directly what

Important to know what from a drug

we use this info how

A

care that a nurse provides directly affects the pharmacokinetics of a medicine
-Covering a patient in a warm blanket reduces stress hormone levels and increases blood flow  directly influencing a drug’s movement within the body

It is also important to know what to expect from a drug response in order to recognize problems

We use this information to our benefit when trying to solve problems

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36
Q

Plasma membranes

  • Passive diffusion (and what are the three traits)
  • Active transport (3 traits also)
A

In order to move within the body, drugs must pass through plasma membranes; they do this either by:

Passive diffusion – moving from an area of high concentration to an area of lower concentration; does not require energy
-Small, non-ionized, lipid soluble drugs can pass through a membrane using passive diffusion

Active transport – moving against the concentration gradient; requires energy (ATP – adenosine triphosphate)
-Large, ionized, non-lipid soluble molecules use carrier proteins or send a messenger within a cell via a receptor

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37
Q

Passage of a drug depends on (3)

What kind of drugs can pass through using passive diffusion

A
  1. Size of drug molecule
  2. Ionization of a drug molecule
  3. Lipid solubility of a drug molecule

Small, non-ionized, lipid-soluble drugs can pass through a membrane using passive diffusion

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38
Q

Pharmacokinetics

Absorption

  • what is it
  • forms
  • what is a large factor
A

Absorption is the process of moving a drug from the site of administration to the bloodstream

-Oral, injection, topical, sublingual, buccal, inhalation

A large factor in determining a drug’s onset of action (the time it takes for a drug to become effective)

  • Fast absorption = Fast onset (IV)
  • Slow absorption = Slow onset (IM)
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39
Q

Absorption

what are the 8 factors
RDDGBDDS

A 
Route of administration
Drug formulation
Drug dosage
Gastrointestinal (GI) tract environment
Blood flow to absorption site
Drug ionization
Drug interactions
Surface area
40
Q

Route of Administration 3 routes

A

Enteral, topical, parenteral

41
Q

Route of Administration

Enteral Route

  • Delivered to
  • Oral and NG susceptible to?
  • Buccal and sublingual work how
A

Enteral Route

  • Delivered to GI tract
  • Includes oral (PO), buccal, sublingual (SL), nasogastric (NG) tubes (and sometimes rectal)
  • Oral and NG – susceptible to gastric acid, enzymes, first pass effect, ability to swallow
  • Buccal (cheek), sublingual (under tongue) – absorbed through mucosa of oral cavity – avoids acid, enzymes and first pass effect

First pass effect is drug enters the liver and undergoes extensive biotransformation and thus decreasing the concentration rapidly before it reaches its target.

42
Q 
Route of Administration 
Topical route is what
-includes
-used how
-Generally slower what
-how do you use the characteristics to our advantage
-what happens if area is compromised
A

Topical Route – delivered to skin or mucous membranes

  • Includes skin, eyes, ears, inhalation, vagina, (and sometimes rectum)
  • Usually used for direct application (antibiotic for skin infection, inhalation for asthma)
  • Generally slower absorption, less presence of drug in blood
  • We use these characteristics to our advantage, to prolong duration of action (nitroglycerin patches) or to minimize side effects (inhaled corticosteroid)
  • IF the area is compromised (abrasion, open sore - we see higher absorption  toxicity)
43
Q

Route of Administration

Parenteral Route is what

  • includes
  • avoids
  • SC, intradermal limited by
  • IM
  • IV
A

Parenteral Route – anything other than enteral or topical
-Includes intravenous (IV), intramuscular (IM), subcutaneous (SC), intradermal, intraperitoneal (IP), intra-arterial, intra-osseous (bone), intrathecal (spinal canal), intraocular
-Avoids gastric enzymes, acidity, and first pass effect
SC, intradermal – limited by small volume
-IM – larger volumes, faster absorption but often use depot injections
-IV – fastest onset and most dangerous (adverse effects, cannot reverse)

44
Q

Drug Formulation

  • forms of tablet
  • liquid
  • tablets/capsules can be coated with?
  • What is extended release
  • what is an ODT
  • What is an IM depot formulated with
A

Is the drug a tablet, capsule, liquid, aerosol, disintegrating tablet?

  • Liquid formulations dissolve faster and absorb faster than solid formulations (liquid > solid)
  • Tablets or capsules can be enteric-coated – coated to withstand acid of stomach, and not dissolve until in small intestine
  • Extended Release – designed to dissolve slowly, to lengthen duration of action (XR, SR, XL, CR)
  • Oral disintegrating tablets (ODT) or films are formulated to dissolve in mouth with no water
  • IM depot injections are formulated in an oily, viscous base to promote slow and continuous absorption from muscle
45
Q

Drug Dosage

-what do high doses do

A

Higher doses or concentrations absorb faster and provide a faster response than lower doses or concentrations

46
Q

GI Tract Environment

  • most absorption occurs
  • slower motility causes?
  • Faster causes?
  • Fatty food do what
  • Acidic/basic drugs need?
A
  • Most absorption occurs in small intestine – depends on gastric motility, pH level
  • Slower motility may leave drug more susceptible to enzymes in stomach
  • Faster motility may reduce absorption by speeding drug along before absorption occurs
  • Fatty foods usually slow drug absorption

Acidic drugs need acidic environment to absorb..
Basic drugs need basic environment to absorb…

47
Q

Blood flow to Absorption site

  • Drugs absorbed faster from
  • what areas
  • ice packs and heat does what
A

Drugs are absorbed faster from areas of the body where blood flow is high

Muscles, buccal cavity, vagina, rectum
Ice packs = vasoconstriction = slower absorption
Heat = vasodilation = faster absorption

48
Q

Drug Ionization

  • ionized means
  • non-ionized means
  • acidic/basic drugs need what sort of ionization

Buffered Asprin

  • Small amounts of an antacid like what are added to product to what
  • Antacid would do what to PH therefore doing what
A

Ionized = a positive or negative charge
Non-ionized = no charge
Depends on pH of environment

Acidic drugs need an acidic environment because they are non-ionized

Basic drugs need a basic environment because they are non-ionized

Small amounts of an antacid like calcium carbonate or aluminum hydroxide are added to the product to help treat or prevent heartburn or upset stomach

  • Antacid would increase/decrease ph surrounding environment
  • therefore increasing/dereasing absorption of ASA
49
Q

Drug Interactions

  • What is a drug drug interaction
  • What is a drug food interaction
A

Drug-drug interaction = tetracycline capsule + calcium carbonate (CaCO3) = delays absorption (bind to make a molecule too large to pass through plasma membrane)
-Not all drug interactions occur at the receptor level

Drug-food interaction = high fat meal + carbamazepine = higher rate of absorption

50
Q

Surface Area
-Larger surface area =?
Examples

A

Larger surface area = faster absorption

Examples: skin, villi and microvilli of small intestine, lung

51
Q

What is bioavailability

-expressed as

A

Bioavailability is the fraction of an administered dose of an unchanged drug that reaches the site of action
Expressed as “F”
For IV drugs, F = 100% (no absorption!)

All absorption variables effect the drug

52
Q

Distribution

  • what is it
  • drugs interacts with
  • changed how
A

Distribution describes how drugs are transported throughout the body

Drugs interact with blood components and move throughout the entire body after they are absorbed

May be chemically and physically changed before they reach the target tissue/area

53
Q

Variables that influence distribution

BDTDB

A 
Blood flow to tissues
Drug solubility
Tissue storage
Drug-protein binding
Barriers
54
Q

Blood Flow to tissues

-which tissues receive highest exposure

A

Highly perfused tissues and organs receive the highest exposure to absorbed drugs
-Heart, liver, kidneys = highest blood flow

Example: treating a fungal infection of toenail with an oral antifungal takes a long time because of poor perfusion
Drug is not distributed to the site of action

55
Q

Drug Solubility

  • Lipid cross what easier and therefor what
  • water has more what
A

Lipid-soluble drugs cross plasma membranes easier and are therefore distributed more broadly throughout the body

Water-soluble drugs have more barriers – more difficult to cross plasma membranes

56
Q

Tissue Storage
-what does tissue do sometimes
-This depends on?
-

A

Some tissues can accumulate and store drugs

Depends on a drug’s affinity (the force by which atoms are held together - strength of attraction )

Example: lipid (fat)-soluble vitamins (A, D, E, K) can accumulate in adipose (fat) tissue and cause toxicity

57
Q

Drug Protein Binding

  • what proteins circulate in our blood
  • drugs do what with these proteins
  • complex have what trouble with PM
  • Complexes can prevent?
  • What drugs act at target site
  • Expressed as what
A

-Protein such as albumin circulate in our blood
-Drugs can bind to proteins, creating a complex
-Complexes are often too large to then cross a plasma membrane and remain ‘trapped’ in the blood stream
-Complexes can also prevent binding to a receptor (doesn’t fit anymore)
-Only free or un-bound drug can act at (or get to) their target site
-Expressed as a %
Example: warfarin is 99% plasma-protein-bound

58
Q

Barriers

What is the blood brain barrier

what is the fetal placental barrier

A

Blood-brain barrier (BBB) = to protect the brain from toxic substances or pathogens

  • Some drugs cross it, others can’t
  • Example: dopamine and levodopa

Fetal-placental barrier = protects baby from harmful substances or pathogens
-Not as efficient as BBB – most drugs cross it, even by a small fraction (alcohol, caffeine)

59
Q

Metabolism

  • What is it
  • How many pathways
  • What kind of chemical reaction is
  • Which is more active (metabolite or molecule)
  • What is a prodrug
A

-Metabolism is a process that changes the activity of a drug and makes it more likely to be excreted
-Hundreds of different pathways
-In general, it is a chemical reaction that makes a molecule more water-soluble, so that it can be excreted in the urine
-Usually, a metabolite (product of metabolism) is less active than the original molecule
-A prodrug is a metabolite that is more active than the original molecule
Example: codeine is given PO =morphine (exerts analgesic effect)

60
Q

Variables that influence metabolism 2

A

Hepatic enzymes

Patient variation

61
Q

Hepatic enzymes

Cytochrome P450 System (CYP450)

  • What is it
  • main site
  • CYP450 is what
  • change in enzyme activity does what
A
  • Cytochrome P450 System (CYP450) is responsible for most metabolism of drugs, nutrients, and endogenous substances
  • Liver is main site, but does occur elsewhere

-CYP450 is a family of enzymes, each assigned a name
CYP1A2, CYP3A4, CYP2C19, etc.

-Changes in enzyme activity alter drug action
The result of the change depends on whether the drug is a substrate, an inducer, or an inhibitor of the CYP450 system

62
Q

Hepatic Enzymes

What is a substrate
what is an enzyme inducer
what is an enzyme inhibitor

A
  • Substrate = the substance on which an enzyme acts; when a drug is metabolized by a CYP450 enzyme
  • Naproxen is a substrate for 2C9 (naproxen = 2C9 =inactive metabolite)

-Enzyme Inducer = when a drug has the ability to increase (speed up) metabolic activity in the liver
Phenobarbital induces 2C9, therefore changing the metabolism of naproxen (decreased naproxen activity)

-Enzyme Inhibitor = when a drug has the ability to decrease (slow down) metabolic activity in the liver
Fluconazole inhibits 2C9, therefore changing the metabolism of naproxen (increased naproxen activity)

63
Q

Hepatic Enzymes

  • Inducers do what
  • Inhibitors do what
A

Drug - metabolized by enzymes - inactive metabolite

Prodrug - metabolized by enzymes - active metabolite

Inducers speed up metabolism

Inhibitors slow down metabolism

64
Q

Hepatic Enzymes

What is the First pass effect

A

When a drug is absorbed from the stomach or small intestine, it enters the portal vein and travels to the liver before it enters circulation and is distributed to other body tissues

Some drugs can be completely converted to an inactive form before it even reaches the general circulation – this drug would have a high first-pass effect

Buccal avoids first pass effect

65
Q

Patient Variation

  • Infants and liver disease
  • Smoking and chronic alcohol use
  • Genetic variations
  • What is pharmacogenomics
A

Infants and patients with liver disease have lower hepatic enzyme activity = require lower doses

Smoking and chronic alcohol consumption tends to induce hepatic enzyme = may require higher doses

Genetic variations cause “slow metabolizers” and “fast metabolizers”

Pharmacogenomics is a fast-developing area of research – customize therapy according to DNA

66
Q

Excretion

  • What does it do
  • What is the rate of which a drug is exerted determine
  • Anything that affects the organ responsible for a drug elimination will do what
A

Excretion processes remove drugs from the body

The rate at which a drug is excreted determines its concentration in the blood and ultimately, its duration of action (the length of time a drug is effective)

Anything that affects the organ responsible for a particular drug’s elimination, will affect that drug’s rate of elimination

67
Q

Name four forms of excretion

A

Renal Excretion
Pulmonary Excretion
Glandular Secretion
Fecal and Biliary Excretion

Often a combination

68
Q

Renal Excretion

  • How much blood does the kidney filter a day
  • What is filtrate
  • What are the three ways it eliminates drugs
  • What does impairment of the kidney do
  • Name factors that effect the renal
  • Pharmacists measure kidney function using?
A

Kidneys filter 180L blood every day

Filtrate = urine

Eliminates drugs through:

  • Filtration – drugs move blood = filtrate in the glomerulus
  • (Reabsorption) – drugs move back from filtrate = blood
  • Secretion – drugs that were not filtered move blood = filtrate

Impairment of kidney function dramatically changes the pharmacokinetics of a drug = usually results in a diminished ability to excrete medications, prolonging duration of action, causing accumulation and toxicity

Also effected by pH (acid-base balance) and electrolyte and fluid balance of patient

Pharmacists measure kidney function using serum creatinine (SCr), which we use to calculate Creatinine Clearance (CrCl) (an estimate for kidney function)

69
Q

Pulmonary Excretion

  • Primary route for what
  • Rapid breathing leads to
  • Alc is partially excreted from?
A

Primarily route of excretion for anesthetics

More rapid breathing leads to faster excretion rates

Alcohol is also partially excreted from the lungs (breathalyzer tests)

70
Q

Glandular Secretion

  • 3 kinds secretion
  • explains what mouth things
  • drugs can do what to sweat
  • how much elimination
  • what is significant when advising breast feeding mothers
A

Saliva, sweat, or breast milk

Explains “bad taste” or garlic breath

Some drugs can colour sweat (rifampin colours all secretions a reddish-orange)

Usually a minimal amount of elimination

Breast milk secretion is significant when advising breast-feeding mothers

71
Q

Fecal and Biliary Elimination

  • some drugs do what with the FB system
  • What is enterohepatic Recirculation
A

-Some drugs are not absorbed at all and are excreted in feces
(Mebendazole for intestinal worms)

Enterohepatic Recirculation occurs when a drug is excreted in the bile to duodenum and then reabsorbed and circulated back to liver (multiple times)
(Explains longer duration of action than what we would expect (in calculations))

72
Q

Time-Response Relationships

  • Therapeutic response of most drugs depends
  • How do you measure the amount of drug
  • Do we need lab tests for every drug
A

The therapeutic response of most drugs depends on their concentration in the plasma

It’s impossible to measure the amount of drug that is present at the target tissue, so instead we take a serum lab test

We don’t need lab tests for every drug – only those with a narrow therapeutic index (a very small window between effective and toxic dose) require Therapeutic Drug Monitoring

73
Q

Plasma Half Life (t1/2)

  • What is it
  • Short half lifes are good for?
  • Long half lifes are good for?
A

The length of time required for a drug’s concentration to decrease by ½ (1-2 minutes or months)

Drugs with short t½ are good for short/minor conditions or procedures
-Anesthetic for dental procedure

Drugs with long t½ are good for chronic conditions
-Felodipine for heart failure can be given once daily

74
Q

Maintaining Therapeutic Range

  • Most drugs require?
  • Another dose should be given before when?
  • We reach the plateau in how many t1/2
A

Most conditions require repeated dosing in order to keep drug plasma concentrations within the therapeutic range

Another dose should be given before the minimum effective concentration is reached = our goal is a plateau drug plasma level

We reach plateau in approximately 4 t½ of the drug if we give equal doses

75
Q

Loading & Maintenance Dosing

what is a Loading Dose?
What is a maintenance dose?

A

Loading dose = allows us to reach plateau levels faster by giving a larger dose

Maintenance dose = the dose required to maintain drug in therapeutic range, given repeatedly

76
Q

Peaks & Troughs

  • What does therapeutic drug monitoring include
  • Peaks should be below what
  • Troughs should be above what?
A

Therapeutic Drug Monitoring may include an attempt to see peaks and troughs of drug concentration – very particular about timing from time of administration

To make sure peaks are below toxic levels, and troughs are above minimal effective levels (within the therapeutic window)

77
Q

Pharmacodynamics

  • Refers to what
  • What is it more concerned with
  • Important in what
A

Refers to how a drug changes the body

More concerned with mechanisms of action and relationship between drug concentrations and responses in the body

Important in providing safe and effective treatment to patient

78
Q

PK vs PD
What is pharmacokinetics
what is pharmacodynamics

A

Pharmacokinetics = what the body does to the drug

Pharmacodynamics = what the drug does to the body

79
Q

Frequency Distribution Curve

  • Representation of?
  • Shows what
  • Does not describe what?
A
  • A graphical representation of the number of patients responding to drugs at different doses
  • Shows whether a measurable response occurred
  • Does not describe the magnitude of the response
80
Q

Median Effective Dose (ED50)

  • Dose required to do what
  • Referred to as?
  • We need to remember that this avg applies to whom
  • 25% responded at what and what
A

The dose required to produce a specific therapeutic response in 50% of a group of clients

Often referred to as standard or average dose

We need to remember that this average dose only applies to half the population
-Average doses do not apply to everyone

25% responded at a lower dose, 25% responded at a higher dose

81
Q

Median Lethal Dose (LD50)

  • Dose that would be?
  • The larger the difference between the ED50 and the LD50 the greater the what
  • Drugs with narrow therapeutic index require what?
A

The dose of a drug that would be lethal in 50% of a group of animals (determined in pre-clinical studies)

The larger the difference between the ED50 and the LD50, the greater the therapeutic index (safety margin)

Drugs with a narrow therapeutic index often require therapeutic drug monitoring

82
Q

Median Toxicity Dose (TD50)

  • Do we test this
  • Where do we find this data
  • Dose required to produce a given what
A

We don’t test the lethal dose in humans (not ethical)

Instead, we either extrapolate data from animal trials or determine toxicity from adverse effects reported in clinical human trials

The dose required to produce a given toxicity in 50% of a group of patients

83
Q

Dose response relationship

  • Looks at what
  • What are the 3 phases
A

Looks at an individual’s response to a drug

Phase 1 – very few target cells have been affected by the drug

Phase 2 – shows the linear relationship between amount of drug administered and degree of response obtained

Phase 3 – plateau, where no further response occurs with a higher dose

  • How? Theories: all receptors are occupied, already obtained 100% relief
  • Even though no further response occurs, we will see adverse effects and signs of toxicity
84
Q

Potency

  • What is it
  • A drug is more potent will produce what
A

Potency = a measure of drug activity or “power”

A drug that is more potent will produce an identical therapeutic effect at a lower dose compared to another drug in the same class

85
Q

Efficacy

  • is what
  • A drug has more efficacy if it?
A

Efficacy = the ability to produce the desired result; the magnitude of maximal response that can be produced from a drug

A drug has more efficacy if it produces a higher maximal response than another drug

86
Q

Potency Vs. Efficacy

  • Which do we value more
  • Drugs with higher potency allow what
A

We usually value drugs with more efficacy
-A patient would choose a drug that is more effective at killing cancer cells than one that is more potent

Drugs with higher potency allow us to be more efficient with prescribing
-We can switch opioids to a more potent drug when we have seen toxicity of a lower potency drug

87
Q

Drug Receptors

  • What is it
  • Cells receive info how
  • What is a ligand
  • forms of endogenous ligands
  • What does the activation of a receptor cause
  • A drug binds to what do cause what?
  • Receptors often have what?
  • Name the two things receptors may be on
A

What a drug does once it gets to the target site

Cells receive information from their environment through receptors

Ligand = a molecule that binds to a receptor

Endogenous ligands: hormones, neurotransmitters

Activation of a receptor causes some sort of cell response, which changes an existing physiological and biochemical process

A drug binds to a receptor to cause a change in body chemistry or physiology

Receptors often have sub-types (α,β), which allow drugs to be more specific for a desired activity (α2-blockers)

  • Receptors may be on a plasma membrane of a cell, allowing entry of chemical into a cell (Na+, K+, ATP pump), or activate a second messenger within a cell
  • Receptors may also be intracellular, affecting protein synthesis or DNA replication of a cell (some antibiotics)
88
Q

Drug Receptors

  • What is an affinity
  • Some drugs have a higher affinity for?
  • Do drugs work together well?
  • What is an agonist
  • What is a partial agonist
  • what is an antagonist
A

Affinity = the force by which atoms are held together - the strength of attraction between a receptor and a ligand (like a magnet)

Some drugs have a higher affinity for a receptor than an endogenous substance= can displace (some estrogens)

Some drugs compete with each other for a receptor (a common drug interaction)

Agonist = a drug that produces the same type of response as an endogenous substance (> or = response)

Partial Agonist = a drug that produces a weaker response (but still a response) than an endogenous substance (lower efficacy than agonist)

Antagonist = a drug that binds to a receptor and does not induce a cell response (BLOCKER)

89
Q 
Drug interactions
-These occur when?
Can be:
-Pharmacokinetic affect? (ADME)
-Pharmacodynamic affect?
A

A drug interaction occurs when a substance increases or decreases a drug’s actions

Can be:
Pharmacokinetic: affects absorption, distribution, metabolism or elimination

Pharmacodynamic: affects the action at the receptor

90
Q

Pharmacokinetic Drug Interactions

Pk Variable
-type of interaction

Absorption:

  • Presence of food
  • Alteration of pH
  • Drug-drug binding
  • Increased peristalsis
  • deceased gastric emptying

Distribution
-Displacement of drug from plasma protein binding site

Metabolism

  • Enzyme induction
  • Enzyme inhibition

Excretion

  • Increased excretion
  • Decreased Excretion
A

Potential drug Effect

A:
Lower
Variable
Lower
Variable
Variable

D:
Increased

M:
Decreased
increased

E:
Decreased
Increased

91
Q

Pharmacodynamic Drug Interactions

  • What is an additive effect
  • What is a synergistic effect
  • What is an antagonistic effect
  • Antagonistic drugs can be used as?
A

Additive effect: two drugs that provide the same therapeutic action are combined (two antihypertensives)

Synergistic effect: the effect of two drugs combined is greater than would be expected than just adding the two individual drug’s actions together (Bactrim® - sulfamethoxazole & trimethoprim)

Antagonistic effect: two drugs that have opposite effects (epinephrine + β-blocker; immuno-suppressant + immuno-stimulant)

-Can reduce adverse effects or work as an ‘antidote’

92
Q

Drug Food interaction

  • What kind of Pharm nature do they possess
  • Grapefruit juice does what
  • Tyramine does
  • Vitamin K does?
A

Grapefruit Juice – inhibits CYP3A4

Tyramine – an amino acid; normally metabolized by MAO (monoamine oxidase); when MAO is inhibited, tyramine crosses into circulation = hypertensive crisis4

Vitamin K – in green, leafy vegetables; a known clotting factor; directly opposes anticoagulant effect of warfarin

93
Q

Drug Tolerance

  • What is the mechanism
  • What is tolerance
  • What does it have to do with opioids
A

The continuous or repeated exposure to agonists can reduce the number of receptors present = down-regulation
-Often the mechanism responsible for drug tolerance

Tolerance = increasing doses of a drug are required to produce the same magnitude of effect

Opioids – often need a higher dose to provide equivalent analgesia

94
Q

Drug Dependence & Withdrawal

  • Physical dependence occurs when (can also be?)
  • What happens when they don’t take it
  • Symptoms of withdrawal?
A

Physical dependence on a drug occurs when the body adapts to repeated use of the substance and view the medication-altered environment as normal
-Can also have psychological dependence

When someone dependent on a drug stops taking it, they experience withdrawal

Symptoms of withdrawal are generally the opposite of the drug’s intended effect (benzodiazepine withdrawal causes anxiety)

95
Q

Dependence Vs. Addiction

  • Addiction is used in what way
  • What are the four Cs of addiction
  • Difference between Dependence and addiction
  • A person can be???? but not ????
A

“Addiction” is used in a very vague way

One way to define addiction is the presence of 4 C’s:

  • Craving
  • Loss of control of amount or frequency of use
  • Compulsion to use
  • Use despite consequences

Dependence on a drug is a physiological matter – and addiction may occur, in part, due to dependence on a drug and the fact that withdrawal may occur upon discontinuation
-Addiction is more psychological

A person can be dependent, but not addicted to a drug

Pharm 250 (3 decks)

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