Week 1 - Intro Flashcards

1
Q

Why do PTs care about pharmacology?

A

Will work with people who are on medications so is good to be aware of the effects.

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2
Q

How do drugs impact rehab? (6)

A
  1. Response to Exercise
  2. Patient’s Pain Perception
  3. Participation and Motivation in Rehab
  4. Interaction with Modalities
  5. Side Effects Screening
  6. Understanding of current medical management in inter-professional care
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3
Q

What is an example of a drugs impacting rehab by response to exercise?

A

Cardiac agents limiting exercise.

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4
Q

What is an example of drugs impacting rehab by patient’s pain perception?

A

Pain management may be necessary to allow/encourage a patient to commit to PT.

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5
Q

What is an example of drugs impacting rehab by participation and motivation in rehab?

A

Pain management and antidepressants

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6
Q

What is an example of drugs impacting rehab by interactions with modalities?

A

Herbal supplements are drugs and can interact with regulated pharaceuticals.

SJW induction of metabolism.
Fentanyl patch and heat wraps.

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7
Q

What is an example of drugs impacting rehab by side effects screening?

A

PT is an important part of integrated health care.
Prolonged, regular patient contact.
-Need to be aware of adverse drug events that are/are not related to PT interventions.

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8
Q

What is an example of drugs impacting rehab by understanding of current medical management in interprofessional care?

A
  • Mainly editorial, perspective, commentary, observational, case-report driven articles found in PT-related journals.
  • Controlled studies found in physician specialty-related literature.
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9
Q

What is the definition of a drug?

A

Any non-nutrient chemical which has a physiological effect on the body.

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10
Q

In what ways can a drug alter physiological function?

A

Increases the function or decreases it.

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11
Q

What are the three types of drugs?

A

1) Natural (doesn’t mean safe)
2) Semi-synthetic (start with known drug)
3) Synthetic (designed in lab)

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12
Q

Describe the semi-synthesis of amoxicillin. Why do it?

A

Penicillin G -> 6-aminopenicillanic acid -> Amoxicillin

  • Improve potency
  • Absorption (in GI tract)
  • Stability (easier to formulate)
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13
Q

What is Pharacotherapeutics?

A

The use of specific drugs to prevent, treat, or diagnose disease.

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14
Q

What is Pharmacokinetics?

A

Study of how the body processes a drug.

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15
Q

What is Pharmacodynamics?

A

Analysis of drug mechanism and effects.

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16
Q

What is Toxicology?

A

Study of the harmful effects of chemicals.

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17
Q

What is a “Generic” (USAN - US adopted name) drug?

A
  1. Often the easiest way to refer to a drug.
  2. Typically less expensive.
  3. Should meet *BioEquivilancy criteria
  4. Even with testing patients don’t always respond the same as to Brand Name
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18
Q

What is a Brand Name drug?

A
  1. Similar trade names for drugs in very different classifications.
  2. May not bear any resemblance to chemical or generic terminology.
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19
Q

What is Bioequivalncy?

A
  1. Same amount and type of active ingredients
  2. Same administration route
  3. Same pharmacokinetic profile
  4. Same therapeutic effect
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20
Q

Suffixes

A

?

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21
Q

What are the benefits to OTC drugs?

A
  1. Lower drug doses
  2. Increased availability/access
  3. Less Expensive (but may be more cost to patient?)
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22
Q

What are the negatives to OTC drugs?

A
  1. Possible interactions with prescription medications.
  2. May delay use of more effective medications or treatment (ibuprophen instead of PT)
  3. Adverse effects.
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23
Q

What are 3 purposes of drugs?

A
  1. Target a specific cell type or tissue type
  2. Some change cellular function to restore a normal state (psychiatric drugs)
  3. Some prevent diseases from occurring (statins prevent buildup of cholesterol)
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24
Q

What is a dose?

A

The amount of drug administered in a given formula.

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25
Q

What is the result of a given dose?

A

a given blood concentration. some linear relationship, blood concentration x2 = x2 dose

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26
Q

What is the result of a given blood concentration?

A

a given concentration at the target tissue.

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27
Q

Why is a given concentration at target tissue important?

A

Concentration must be large enough to produce a benefit without being toxic (exceptions like chemo)

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28
Q

What does a dose-response curve represent?

A

the dosage over which the drug is effective and peak effect/response that can be expected. Shape of curve and plateau indicate info re: binding of drug to cellular receptors.

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29
Q

What is a threshold dose?

A

Where response begins and increases in magnitude until a response plateau is reached.

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30
Q

What is a ceiling effect (maximal efficacy)?

A

the point at which there is no further response (even if dosage continues to be increased.)

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31
Q

What is efficacy?

A

Dosage ranges over which the drug has desired effect.

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32
Q

Magnitude of response increases as ____

A

dosage increases (up to some maximal effect)

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33
Q

What is potency?

A

Threshold dose that produces a given response.

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34
Q

Higher potency means ____

A

less of the compound is required to produce a given response.

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35
Q

Lower threshold dose =

A

increased potency

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36
Q

T/F: Potency or Maximum Efficacy can indicate a drug’s theraputic potential.

A

FALSE: neither potency nor maximum efficacy fully indicate a drugs therapeutic potential.

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37
Q

Graph: Which drug is more potent?

A

Drug “A”

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38
Q

Which drug has the greater maximal effect?

A

Drug “B”

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39
Q

What is a Quantal Dose-Response Curve?

A

% of the population who exhibit a specific response relative to the dose of the drug.

looks at variations in drug responses due to individual differences within the clinical population.

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40
Q

How do you calculate a therapeutic index?

A

TI = TD50/ED50

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41
Q

What is a therapeutic index (TI)?

A

calculated value to indicate drug safety.

  • relative term, higher TI = considered safer
  • prescription ages usually lower TIs

(extremely low TI wouldn’t be approved unless for cancer of perhaps HIV)

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42
Q

What is Median Effective Dose (ED50)?

A

The dose at which 50% of the population responded to a drug in a specific manner (response).

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43
Q

What is Median Toxic Dose (TD50)?

A

The dose at which 50% of the population exhibits the adverse effect/response.

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44
Q

What is the Median Lethal Dose (LD50)?

A

The dose that causes death in 50% of the animals studied.

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45
Q

What does the food and drug administration do?

A
  • Began in the early 1900s
  • Is a Drug Effective?
  • Is a Drug Safe?
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46
Q

What is drug approval process?

A
  • Clinical Testing Phases: I - IV
  • 7-9 years (~1 billion dollars total cost)
  • ‘Fast Track’ exists for life-threatening conditions or approval of a new indication ofr a known drug.
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47
Q

What are the phases for clinical testing?

A
Pre-Clinical Testing: lab animals
Phase I - Clinical Testing: healthy subjects
Phase II - Limited target population
Phase III - Large target population
*New Drug Approval* (NDA)
Phase IV: Monitor general popultion
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48
Q

Based on The Coprehensive Drug Abuse Prevention and Control Act. (1970) what are categories or “schedules” for?

A

classified according to potential for abuse.

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49
Q

Which schedule of drug has the highest abuse potential?

A

I

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50
Q

Which schedule of drug has the lowest abuse potential

A

V

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51
Q

Schedule I:
Abuse Potential -
Legal Use -
Example -

A

Schedule I:
Abuse Potential - highest
Legal Use - restricted to approved research or therapeutic use in very limited number of patients
Example - medical marijuana, coccaine

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52
Q

Schedule II:
Abuse Potential -
Legal Use -
Example -

A

Schedule II:
Abuse Potential - high
Legal Use - specific therapeutic purposes w/ prescription
Example - Opoids: morphine

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53
Q

Schedule III:
Abuse Potential -
Legal Use -
Example -

A

Schedule III:
Abuse Potential - mid-moderate possible physical/psychologic dependence
Legal Use - specific therapeutic purposes w/ prescription
Example - certain opiods: codeine combos; anabolic steroids

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54
Q

Schedule IV:
Abuse Potential -
Legal Use -
Example -

A

Schedule IV:
Abuse Potential - limited possible physical/psychologic dependence
Legal Use - specific therapeutic purposes w/ prescription
Example - Anti-Anxiety drugs; Other depressants and stimulants

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55
Q

Schedule V:
Abuse Potential -
Legal Use -
Example -

A

Schedule V:
Abuse Potential - lowest relative abuse potential
Legal Use - OTC
Example - cough medications; anti-diarrheal medications

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56
Q

What is pharmacodynamics?

A

How a drug affects the body (time course and intensity of effect)

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57
Q

What is pharmacokinetics?

A

How the body affects the drug (absoprtion, distribution, metabolism, and excretion)

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58
Q

What is therapeutic effects: subtherapeutic

A

not enough of the drug to see what you want to see

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59
Q

What is therapeutic effect: supratherapeutic

A

too much of the drug and get into more toxic effects

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60
Q

What does pharmacodynamics determine?

A

Optimal Therapy:

Sub-therapeutic –> Therpeutic Dose –> Toxicity

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61
Q

How does Sub-therapeutic –> Therpeutic Dose –> Toxicity correlate with blood plasma concentration of drug?

A

Increasing blood plasma concentration of drug with increase in dose

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62
Q

More potent drug = ___ drug required for a specific response

A

More potent drug = LESS drug required for a specific response

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63
Q

T/F: Potency = Efficacy

A

FALSE: Potency does not equal efficacy

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64
Q

What is efficacy?

A

drug’s ability to produce a desired response (inherent to drug)

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65
Q

What is effectiveness?

A

describes how useful the drug is (TI, ease of use)

more of a real world definition based on how difficult to take and the side effects

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66
Q

What is maximal efficacy (ceiling effect)? Example?

A

increase in dose produces no greater response than a lower dosage (saturate receptors)

(I.E. beta blockers for blood pressure control)

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67
Q

What goes into the nature of drug binding?

A

Sterics - must match fit

electronics - must match charges

68
Q

What are the 4 factors of pharmacokinetics?

A
  1. Administration
  2. Absorption
  3. Distribution
  4. Elimination (also metabolism)
69
Q

What are the routes of drug administration? (12)

A
  1. Sublingual
  2. Rectal
  3. Oral
  4. Inhaled
  5. Injection
  6. Intravenous
  7. Intra-arterial
  8. Sub-Cutaneous
  9. Intra-Muscular
  10. Transdermal
  11. Topical
  12. Intrathecal
70
Q

Transdermal: Route for Rehabilitation Modalities - Phonophoresis and Iontophoresis

A

Used for inflammatory reason, really only time using drugs as PT

Phonophoresis - ultrasound
Iontophoresis - electrical conduction

71
Q

Usually Oral

a. Enteral
b. ParaEnteral

A

a. Enteral

72
Q

Easiest for self-administration

a. Enteral
b. ParaEnteral

A

a. Enteral

73
Q

Bypass the GI system

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

74
Q

What are the two broad methods for entry?

A

a. Enteral

b. ParaEnteral

75
Q

Generally safe, controlled entry to system

a. Enteral
b. ParaEnteral

A

a. Enteral

76
Q

More predictable quantity

a. Enteral
b. ParaEnteral

A

b. ParaEntral

77
Q

Absorbed by small intenstine

a. Enteral
b. ParaEnteral

A

a. Enteral

78
Q

Drug must have high lipid solubility

a. Enteral
b. ParaEnteral

A

a. Enteral

79
Q

What is “First Pass Effect”?

A

metabolism/destruction of drug in liver before reaching site of action, only fraction of does goes into blood stream. Blood supply dumping out of stomach and into SI (so sublingual wouldn’t have this)

80
Q

Subject to first pass effect

a. Enteral
b. ParaEnteral

A

a. Enteral

81
Q

Not subject to “First pass Effect”

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

82
Q

Examples: oral, sublingual, rectal

a. Enteral
b. ParaEnteral

A

a. Enteral

however sublingual is not subject to first pass

83
Q

Examples: injection, IV, IA, Sub-Q, IM, TD, Topical, Intrathecal, Inhaled; Spine

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

84
Q

What is Bioavailability?

A

% of drug administered that reaches the blood stream

85
Q

If you inject 100mg of a drug and 10mg makes it, what is the bioavailability?

A

10/100 = 10% bioavailability

86
Q

What two factors affect bioavailability?

A
  1. Depends on route of administration and the drug’s ability to cross membrane barriers
  2. Depends on extent of first pass metabolism
87
Q

Where can weak acids be absorbed?

A

stomach pH 1 to 3 - drugs are neutral / no overall electronic charge in stomach

88
Q

Where can weak bases be absorbed?

A

Duodenum pH 5 to 7 (cannot passively go through lipid layer in stomach, not neutral in duodenum and be be absorbed where as acids cannot.

89
Q

How are the vast majority of drugs absorbed?

A

Passive Divvusion

90
Q

What are the 4 methods of drug absorption?

A
  1. Passive Diffusion
  2. Active Transport
  3. Facilitated Diffusion (ion or small molecule pumped out and back in)
  4. Endocytosis
91
Q

What 4 things are involved with distribution or moving the drug throughout the body?

A
  1. Tissue Permeability
  2. Blood Flow
  3. Plasma Protein Binding
  4. Subcellular Protein Binding
92
Q

What are 3 factors of tissue permeability?

A
  1. High lipid soluble molecules cross membranes more easily
  2. Solubility concerns
  3. Membrane permeability
93
Q

What are the two factors of blood flow?

A
  1. Bloodstream will carry drugs to highly-perfused organs

2. Can be affected by disease

94
Q

What are the two factors of plasma protein binding?

A
  1. Reversible bonds

2. Bound portion of drug doesn’t have therapeutic effect and is not elimated

95
Q

What is a factor of subcellular protein binding?

A

Drug gets trapped within the cell (usually in the lysosome)

Example: anti-depressants

96
Q

Positive artieriole pressure ____

A

draws drug via blood into tissue spaces

97
Q

Negative venule pressure ____

A

pulls drug from tissue back into blood

98
Q

Drug that is bound to plasma protein cannot leave the blood to distribute into tissues and is ___

A

inactive

99
Q

Drug that is unbound (free) may distribute from blood to tissues and is ___

A

active

100
Q

High Serum Protein Binding

A

Lots of drug will attach to protein but as it is absorbed from the blood into the tissues, drug will be released from protein to establish equilibrium.

101
Q

Low Serum Protein Binding

A

Very soluble so will have a lot free in the blood and available to be absorbed into the tissues

102
Q

What is Vd?

A

volume of distribution = amount of drug administered / concentration of drug in plasma

103
Q

if Vd = Total amount of body water

A

uniform body distribution

104
Q

if Vd > Total amount of body water

A

drug is being concentrated in the tissues

105
Q

if Vd

A

drug is being retained in the bloodstream (due to plasma protein binding for example)

106
Q

If you inject 100mg of a drug into 100ml of water and stir, Vd = ?

A

there will be 1.0mg/ml in the solution and can confirm this by drawing 1.0 mL of water, it will contain 1.0mg of drug

107
Q

Now inject 100mg of a drug into an unknown volume and stir. If we draw 1.0m and find that there is 2.0 mg/mL, how much water was in the box (Vd)?

A

50mL

100mg/50mL = 2 mg/mL

108
Q

Which schedule of drug has the highest abuse potential?

A

I

109
Q

Which schedule of drug has the lowest abuse potential

A

V

110
Q

Schedule I:
Abuse Potential -
Legal Use -
Example -

A

Schedule I:
Abuse Potential - highest
Legal Use - restricted to approved research or therapeutic use in very limited number of patients
Example - medical marijuana, coccaine

111
Q

Schedule II:
Abuse Potential -
Legal Use -
Example -

A

Schedule II:
Abuse Potential - high
Legal Use - specific therapeutic purposes w/ prescription
Example - Opoids: morphine

112
Q

Schedule III:
Abuse Potential -
Legal Use -
Example -

A

Schedule III:
Abuse Potential - mid-moderate possible physical/psychologic dependence
Legal Use - specific therapeutic purposes w/ prescription
Example - certain opiods: codeine combos; anabolic steroids

113
Q

Schedule IV:
Abuse Potential -
Legal Use -
Example -

A

Schedule IV:
Abuse Potential - limited possible physical/psychologic dependence
Legal Use - specific therapeutic purposes w/ prescription
Example - Anti-Anxiety drugs; Other depressants and stimulants

114
Q

Schedule V:
Abuse Potential -
Legal Use -
Example -

A

Schedule V:
Abuse Potential - lowest relative abuse potential
Legal Use - OTC
Example - cough medications; anti-diarrheal medications

115
Q

What is pharmacodynamics?

A

How a drug affects the body (time course and intensity of effect)

116
Q

What is pharmacokinetics?

A

How the body affects the drug (absoprtion, distribution, metabolism, and excretion)

117
Q

What is therapeutic effects: subtherapeutic

A

not enough of the drug to see what you want to see

118
Q

What is therapeutic effect: supratherapeutic

A

too much of the drug and get into more toxic effects

119
Q

What does pharmacodynamics determine?

A

Optimal Therapy:

Sub-therapeutic –> Therpeutic Dose –> Toxicity

120
Q

How does Sub-therapeutic –> Therpeutic Dose –> Toxicity correlate with blood plasma concentration of drug?

A

Increasing blood plasma concentration of drug with increase in dose

121
Q

More potent drug = ___ drug required for a specific response

A

More potent drug = LESS drug required for a specific response

122
Q

T/F: Potency = Efficacy

A

FALSE: Potency does not equal efficacy

123
Q

What is efficacy?

A

drug’s ability to produce a desired response (inherent to drug)

124
Q

What is effectiveness?

A

describes how useful the drug is (TI, ease of use)

more of a real world definition based on how difficult to take and the side effects

125
Q

What is maximal efficacy (ceiling effect)? Example?

A

increase in dose produces no greater response than a lower dosage (saturate receptors)

(I.E. beta blockers for blood pressure control)

126
Q

What goes into the nature of drug binding?

A

Sterics - must match fit

electronics - must match charges

127
Q

What are the 4 factors of pharmacokinetics?

A
  1. Administration
  2. Absorption
  3. Distribution
  4. Elimination (also metabolism)
128
Q

What are the routes of drug administration? (12)

A
  1. Sublingual
  2. Rectal
  3. Oral
  4. Inhaled
  5. Injection
  6. Intravenous
  7. Intra-arterial
  8. Sub-Cutaneous
  9. Intra-Muscular
  10. Transdermal
  11. Topical
  12. Intrathecal
129
Q

Transdermal: Route for Rehabilitation Modalities - Phonophoresis and Iontophoresis

A

Used for inflammatory reason, really only time using drugs as PT

Phonophoresis - ultrasound
Iontophoresis - electrical conduction

130
Q

Usually Oral

a. Enteral
b. ParaEnteral

A

a. Enteral

131
Q

Easiest for self-administration

a. Enteral
b. ParaEnteral

A

a. Enteral

132
Q

Bypass the GI system

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

133
Q

What are the two broad methods for entry?

A

a. Enteral

b. ParaEnteral

134
Q

Generally safe, controlled entry to system

a. Enteral
b. ParaEnteral

A

a. Enteral

135
Q

More predictable quantity

a. Enteral
b. ParaEnteral

A

b. ParaEntral

136
Q

Absorbed by small intenstine

a. Enteral
b. ParaEnteral

A

a. Enteral

137
Q

Drug must have high lipid solubility

a. Enteral
b. ParaEnteral

A

a. Enteral

138
Q

What is “First Pass Effect”?

A

metabolism/destruction of drug in liver before reaching site of action, only fraction of does goes into blood stream. Blood supply dumping out of stomach and into SI (so sublingual wouldn’t have this)

139
Q

Subject to first pass effect

a. Enteral
b. ParaEnteral

A

a. Enteral

140
Q

Not subject to “First pass Effect”

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

141
Q

Examples: oral, sublingual, rectal

a. Enteral
b. ParaEnteral

A

a. Enteral

however sublingual is not subject to first pass

142
Q

Examples: injection, IV, IA, Sub-Q, IM, TD, Topical, Intrathecal, Inhaled; Spine

a. Enteral
b. ParaEnteral

A

b. ParaEnteral

143
Q

What is Bioavailability?

A

% of drug administered that reaches the blood stream

144
Q

If you inject 100mg of a drug and 10mg makes it, what is the bioavailability?

A

10/100 = 10% bioavailability

145
Q

What two factors affect bioavailability?

A
  1. Depends on route of administration and the drug’s ability to cross membrane barriers
  2. Depends on extent of first pass metabolism
146
Q

Where can weak acids be absorbed?

A

stomach pH 1 to 3 - drugs are neutral / no overall electronic charge in stomach

147
Q

Where can weak bases be absorbed?

A

Duodenum pH 5 to 7 (cannot passively go through lipid layer in stomach, not neutral in duodenum and be be absorbed where as acids cannot.

148
Q

How are the vast majority of drugs absorbed?

A

Passive Divvusion

149
Q

What are the 4 methods of drug absorption?

A
  1. Passive Diffusion
  2. Active Transport
  3. Facilitated Diffusion (ion or small molecule pumped out and back in)
  4. Endocytosis
150
Q

What 4 things are involved with distribution or moving the drug throughout the body?

A
  1. Tissue Permeability
  2. Blood Flow
  3. Plasma Protein Binding
  4. Subcellular Protein Binding
151
Q

What are 3 factors of tissue permeability?

A
  1. High lipid soluble molecules cross membranes more easily
  2. Solubility concerns
  3. Membrane permeability
152
Q

What are the two factors of blood flow?

A
  1. Bloodstream will carry drugs to highly-perfused organs

2. Can be affected by disease

153
Q

What are the two factors of plasma protein binding?

A
  1. Reversible bonds

2. Bound portion of drug doesn’t have therapeutic effect and is not elimated

154
Q

What is a factor of subcellular protein binding?

A

Drug gets trapped within the cell (usually in the lysosome)

Example: anti-depressants

155
Q

Positive artieriole pressure ____

A

draws drug via blood into tissue spaces

156
Q

Negative venule pressure ____

A

pulls drug from tissue back into blood

157
Q

Drug that is bound to plasma protein cannot leave the blood to distribute into tissues and is ___

A

inactive

158
Q

Drug that is unbound (free) may distribute from blood to tissues and is ___

A

active

159
Q

High Serum Protein Binding

A

Lots of drug will attach to protein but as it is absorbed from the blood into the tissues, drug will be released from protein to establish equilibrium.

160
Q

Low Serum Protein Binding

A

Very soluble so will have a lot free in the blood and available to be absorbed into the tissues

161
Q

What is Vd?

A

volume of distribution = amount of drug administered / concentration of drug in plasma

162
Q

if Vd = Total amount of body water

A

uniform body distribution

163
Q

if Vd > Total amount of body water

A

drug is being concentrated in the tissues

164
Q

if Vd

A

drug is being retained in the bloodstream (due to plasma protein binding for example)

165
Q

If you inject 100mg of a drug into 100ml of water and stir, Vd = ?

A

there will be 1.0mg/ml in the solution and can confirm this by drawing 1.0 mL of water, it will contain 1.0mg of drug

166
Q

Now inject 100mg of a drug into an unknown volume and stir. If we draw 1.0m and find that there is 2.0 mg/mL, how much water was in the box (Vd)?

A

50mL

100mg/50mL = 2 mg/mL