Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmaceutical Sciences > Exam 1 > Flashcards

Exam 1 Flashcards

1
Q

Define pharmacokinetics

A

the kinetics of drug (1) absorption, (2) distribution and (3) elimination from the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Define pharmacodynamics

A

the relationship between (1) the drug concentration at the receptor and (2) the physiologic response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Define therapeutic window (2 components)

A

the plasma drug concentration at which (a) the drug is effective (b) without [1] exceeding the minimum toxic concentration (MTC)OR [2] falling below the minimum effective concentration (MEC)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Define bioavailability (F)

A

the amount of therapeutically active drug that reaches the systemic circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Define biopharmaceutics (4 components)

A

the interrelationship between (1) physicochemical properties of the drug, (2) the dosage form, (3) the route of administration and (4) how these affect systemic drug absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Define drug substance

A

FDA definition: substance intended for the use in diagnosis, cure, mitigation, treatment or prevention of disease.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are three (3) synonyms for drug substance?

A
  1. Active ingredient
  2. active pharmaceutical ingredient (API)
  3. active constituent
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

By what two (2) properties is a drug substance selected by

A
  1. Physicochemical

2. pharmacological efficacy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

By what two (2) properties is a drug vehicle selected by?

A
  1. ability to overcome physiological barriers

2. enable therapeutically relevant drug delivery from site of administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define drug formulation

A
  1. Active drug substance

2. Active or inactive substances (excipients) in a preparation that is ready to be administered.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Define excipient

A

A usually inert substance that forms a vehicle (as for a drug)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define drug product

A

Finished dosage form including:

  1. formulation
  2. deliver mechanism
  3. packaging
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define drug product performance (2 components)

A

the release of the drug substance from the drug product either for (1) local drug action or (2) drug absorption into plasma for systemic drug therapeutic activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are three (3) factors affecting drug product performance?

A
  1. drug (physicochemical)
  2. dosage form (drug product)
  3. body (individual patient)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Drug Product Performance is divided into what four (4) phases?

A
  1. Absorption - drug enter blood
  2. Distribution - drug moves between blood and tissue
  3. Metabolism - biochemical drug conversion
  4. Excretion - irreversible removal of chemically intact drug
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is disposition?

A

A phase in performance including distribution and elimination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is elimination?

A

A phase in performance including metabolism and excretion.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

How are the phases of drug product performance quantified?

A

Plasma concentration vs Time Curves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are Critical Quality Attributes (CQAs)? (4 components)

A

Critical Quality Attributes (CQA) are (1) chemical, (2) physical, (3) biological and (4) microbiological attributes that can be defined, measured, and continually monitored to ensure final product outputs remain within acceptable quality limits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are Product Quality Attributes?

A

parameters in the manufacturing process

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is drug delivery?

A

A mechanism of the drug product designed to transport a drug to a specific part of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Define drug absorption

A

Series of events leading up to drug appearance in systemic circulation including:

  1. loss before absorption
  2. dissolution and drug release from product
  3. absorption of soluble drug through membranes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are three (3) factors affecting drug absorption?

A
  1. Physicochemical properties of the drug substance
  2. Drug product
  3. Anatomy of the target site of absorption and action
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Why does intravascular (ex. intravenous) administration not involve administration?

A

The drug is delivered directly to blood stream (systemic circulation) and thus does not need to be absorbed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Define the two (2) types of movement a drug can do

A
  1. Transcellular movement: movement across cells

2. Paracellular movement: movement between cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are three (3) transport mechanisms?

A
  1. Passive diffusion
  2. Facilitated diffusion
  3. Active transport
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is permeability?

A

how easy it is for a substance to pass through a membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is flux and in what units is it expressed?

A

Rate of transport for diffusion expressed as (quantity)(time)^-1(area)^-1 (how much water flows from a cross section in a river in a certain time)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Express Fick’s First Law of Diffusion

A

dQ/dt = [(DAK)/h] (Cgi - Cp)

dQ/dt = rate of diffusion
D = diffusion coefficient (area/time)
A = surface area of membrane
K = drug limit water partition coefficient
h = membrane thickness (length of diffusion path)
Cgi - Cp = difference in drug concentration between GI tract and plasma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe passive diffusion as an equation for net rate of penetration

A

Net rate of penetration = Permeability * Surface Area * Concentration Gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is osmosis?

A

The passive diffusion of water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is a saturable process

A

There is a maximum rate (e.g. all channels are full)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is an influx transporter?

A

Transfers substrate into cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is an efflux transporter?

A

Transfers substrate out of cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is an absorptive transporter?

A

Transfers substrate into system circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is a secretive transporter?

A

Transfers substrate from system circulation into bile, urine and/or GI lumen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Define facilitated diffusion

A

Passive transport of a drug (across a membrane) by specific transmembrane proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Define active transport

A

Characterized by the ability to transport a drug against its concentration gradient at the cost of energy.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is a notable influx transporter in the GI tract?

A

PepT1 - influx transporter that can enhance the absorption of peptide drugs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is a notable efflux transporter in the GI tract?

A

P-gp efflux transporter (also called MDR1): has the ability to efflux many different drug molecules out of cells and into the GI lumen.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

MDR1 efflux transporters are especially important in these three (3) areas:

A
  1. GI Lumen
  2. Blood-brain barrier
  3. Drug resistant cancer cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Pharmacodynamics is studied using what type of measurements?

A

Exposure-response measurements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is drug exposure?

A

the dose that is input to the body and the measure of drug concentrations in the plasma and other biological fluids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is drug response?

A

measurement of the physiologic effect that the drug has on the body (measured by clinical markers such as blood pressure, cholesterol elvel, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What are two (2) factors that affect both drug exposure and drug response?

A
  1. Disease state

2. patient-specific factors (age, race, sex, exercise level, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Define dosing regimen

A

Amount and interval of drug administration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What are four (4) invasive methods for measuring drug concentration?

A

1/2. Blood from peripheral vein/artery

  1. Tissue biopsy
  2. CNS fluid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What are peripheral veins/arteries?

A

Veins/arteries that are not part of the abdomen/drunk.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are six (6) noninvasive methods for measuring drug concentration?

A
  1. Urine
  2. Feces
  3. Tears
  4. Sweat
  5. Saliva
  6. Breast milk
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What is a major difference between whole blood and serum or plasma?

A

Serum and plasma do not contain cellular elements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

What is a major difference between serum and plasma?

A

Serum does not contain clotting proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Why are plasma drug concentrations useful for calculating drug kinetics?

A

Plasma perfuses all tissues of the body, thus changes in the plasma drug concentration will reflect changes in tissue drug concentrations.
ASSUMPTION: drug in plasma is in equilibrium with the tissues

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What are two (2) different states that a drug may exist while in plasma (systemic circulation)?

A

Protein-bound or free (unbound)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is AUC and what does it represent?

A
  1. Area Under Curve for a plasma drug [c]-time curve.

2. Represents the calculation of total drug exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is Cmax and what three (3) factors is related to?

A

Peak concentration:

  1. dose
  2. rate constant for absorption
  3. rate constant for elimination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What is Tmax and how can it be interpreted?

A

Time of Peak Concentration: Is a very rough marker of average rate of drug absorption (for oral delivery)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

IV Push gives a simple means for calculating pharmacokinetic parameters. What are two (2) assumptions made in these calculations?

A
  1. No absorption. Drug distributes and equilibrates instantaneously.
  2. Elimination begins to occur immediately.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

In a typical plasma drug [c]-time curve, explain three notable regions in terms of input rate and output rate.

A
  1. Input rate > output rate (part of curve before Cmax)
  2. Input rate = output rate (Cmax)
  3. Input rate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Explain why the phase of the plasma drug [c]-time curve where input rate > output rate increases at a decreasing rate.

A

Disposition occurs shortly after administration, lowering plasma drug [c] by movement into tissues and elimination.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

Define apparent volume of distribution

A

Vd is the volume in which the drug appears to be distributed at equilibrium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

From what two (2) parameters is the apparent volume of distribution calculated?

A
  1. injected amount of drug
  2. plasma drug concentration immediately after injection
    [based on first assumption of IVPush kinetics]
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Define clearance

A

describes the process by which a drug is eliminated from the body without identifying the individual processes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

In what units is clearance reported?

A

Volume of fluid cleared of drug from the body per unit of time (e.g. mL/min, L/hr)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

What two parameters characterize the elimination phase?

A
  1. Elimination half-life

2. Volume of distribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

How is elimination half-life determined?

A

k = ln2/half-life

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

How is total clearance determined?

A

Total Clearance = k*Vd

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

Define drug excretion

A

Removal of intact drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

Define drug metabolism (biotransformation)

A

the drug is chemically converted to a metabolite in the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

Is the body modeled in the calculation of drug clearance?

A

The body is considered as one compartment.

70
Q

What is the elimination rate constant in drug clearance calculation?

A

Sum of all different rate constants for drug elimination

71
Q

What is elimination half-life?

A

The time taken for the plasma concentration to fall by 1/2.

72
Q

How many half-lives must occur for total elimination?

A

5 half-lives eliminate about 97% of drug.

73
Q

What is the kinetic order of the process for the elimination of most drugs?

A

The rate of elimination from the body followers a first-order process.

74
Q

The rate of elimination is proportional to what in first order elimination?

A

Proportional to the plasma [c].

75
Q

When the plasma [c] is plotted vs. time in a first-order process, what is the shape of the curve?

A

Decrease at decreasing rate.

76
Q

When the plasma [c] is plotted vs time on a semi-log graph in a first-order process, what is the shape of the curve?

A

Linear with slope= (-k)/2.3

77
Q

What are three (3) major sites of excretion of the drug/metabolite?

A
  1. Kidney
  2. Liver
  3. Intestine
78
Q

What are three (3) minor sites of excretion of the drug/metabolite?

A
  1. Skin
  2. Lungs
  3. Salivary glands
79
Q

What is steady-state concentration?

A

When the rate of drug input = rate of drug output and the plasma [c] plateaus.

80
Q

What drug administration can easily result in a steady-state concentration?

A

IV Infusion, because the drug will be infused slowly at a constant rate (zero order rate of delivery).

81
Q

What are three (3) advantages of IV infusion?

A
  1. Avoid large peaks and troughs.
  2. Can give the drug with IV fluids
  3. Easy to maintain/adjust or terminate therapy as needed.
82
Q

How does IV infusion induce steady-state concentration? (4 steps)

A
  1. Infusion can be thought of as multiple doses.
  2. Drug accumulates as successive doses are administered.
  3. Rate of elimination increases as plasma [c] increases.
  4. Rate of elimination approaches rate of administration until max and min drug concentrations are the same for two successive doses.
83
Q

On what four (4) parameters does plasma [c] depend on during steady state?

A
  1. Clearance
  2. Volume of distribution
  3. Dose
  4. Dosing interval
84
Q

Define local administration

A

exerts its effect where applied

85
Q

Define systemic administration

A

intended to produce an effect throughout the body; blood circulation required to deliver the drug to its site of action

86
Q

What are three (3) factors on which route of delivery is chosen?

A
  1. Intended site of action
  2. Properties of the drug compound
  3. Patient and disease-specific factors
87
Q

What are three routes of delivery?

A
  1. Parenteral (must be injectable)
  2. Enteral
  3. Other
88
Q

List two (2) classifications of parenteral administrations and give examples for each

A
  1. Intravascular: intravenous, intrarterial

2. Extravascular: intradermal, intramuscular, subcutaneous

89
Q

Give four (4) examples of enteral routes of delivery

A
  1. Oral
  2. Rectal
  3. Sublingual
  4. Buccal
90
Q

Give three (3) examples of “other” routes of delivery

A
  1. Topical
  2. Transdermal
  3. Pulmonary
91
Q

What is the primary goal of Biopharmaceutics?

A

Optimize therapeutic activity and safety outcomes of a drug product using basic sciences.

92
Q

What is Quality by Design?

A

Approach in pharmaceutical development that is systematic and scientific with the final product being kept in mind throughout the process.

93
Q

How do Critical Quality Attributes relate to routes of administration?

A

Different CQAs will apply to each route of administration for therapeutic efficacy and patient safety.

94
Q

Give five (5) examples of performance attributes

A
  1. In vitro: Purity
  2. In Vivo: Efficacy/Safety
  3. Sensory: Taste
  4. Utility: Storage
  5. Administration: Ease of injection
95
Q

What are three (3) Raw material CQAs

A
  1. Particle size and distribution
  2. Bulk density of the material
  3. Hardness of a tablet
96
Q

What are three (3) factors affecting the Critical Quality Attribute of Stability?

A
  1. Environmental factors
  2. Packaging materials
  3. Microbial contamination
97
Q

What are four (4) environmental factors that affect stability?

A
  1. Temperature
  2. Light
  3. Air
  4. Humidity
98
Q

What are the first three rate steps (processes) involved solid oral drug absorption?

A
  1. Disintegration and subsequent drug release
  2. Dissolution of the drug in an aqueous environment
  3. Absorption across membranes
99
Q

Define disintegration

A

The process by which aggregated small particles are liberated, releasing the drug

100
Q

Define dissolution

A

The process by which a chemical or drug becomes dissolved in a solvent

101
Q

Define solubility

A

static property that refers to how much mass of a solute can dissolve in mass or volume of solvent at a given temperature (e.g. 10 g/L)

102
Q

What are five (5) drug product design considerations to meet desired bioavailability and therapeutic objectives?

A
  1. physicochemical properties of molecule
  2. type of drug product
  3. nature of excipients
  4. method of manufacturing
  5. route of drug administration
103
Q

How does biopharmaceutics aid the use of drugs?

A

It allows for the rational design of drug products.

104
Q

What are seven (7) factors for the rational design of drug products?

A
  1. Physicochemical properties of substance
  2. Route of administration
  3. Desired pharmacodynamic effect
  4. Toxicologic properties
  5. Safety of excipients
  6. Effect of excipients and dosage form on drug product performance
  7. Manufacturing processes
105
Q

What is purpose of the Noyes-Whitney Equation?

A

Equation describing the rate of dissolution in terms of properties of the solute and solvent.

106
Q

Write the Noyes-Whitney Equation

A

dC/dt = (DA/h) * (Cs-C)

dC/dt = rate of dissolution
D = diffusion rate constant
A = surface area of particle
h = thickness of stagnant layer 
Cs = concentration of drug in stagnant layer (equal to solubility)
C = concentration of drug in the rest of the solvent
107
Q

Why is the concentration of drug in the stagnant layer equal to the solubility?

A

The stagnant layer is a saturated solution at the surface of the particle.

108
Q

Describe a pH-solubility plot

A

Plot of drug solubility at various pH values.

109
Q

Describe a pH-stability plot

A

Describes the reaction rate constant for degradation of the drug at various pH values

110
Q

How does pH formulation affect drug performance?

A

pH affects solubility and stability.

111
Q

How does particle size affect drug performance?

A
  1. Decreasing particle size will increase surface area that is available for dissolution.
  2. Increased surface area will increase rate of dissolution.

[Noyes-Whitney Equation]

112
Q

What are three (3) common excipients that affect bioavailability?

A
  1. Disintegrants
  2. Coatings
  3. Lubricants
113
Q

How do disintegrants affect bioavailability?

A

enhance the rate of disintegration and dissolution

114
Q

How do coatings affect bioavailability?

A

control release of the drug (affect diffusion rate constants)

115
Q

How do lubricants affect bioavailability?

A

Can slow dissolution rates

116
Q

What are five (5) formulation factors affecting absorption?

A
  1. Dosage form design (drug product)
  2. Rate of drug release from dosage form
  3. Dose
  4. Pharmacokinetics
  5. Route of administration
117
Q

Define duration of effect

A

Timeframe at which plasma [c] exceeds minimum effective concentration.

118
Q

Define onset time

A

Time at which plasma [c] first reaches minimum effective concentration.

119
Q

Describe the relationship between volume of distribution, amount of drug in body and plasma drug [c].

A

Vd is the plasma volume in which the drug appears to be distributed at equilibrium. Therefore, Vd times the plasma drug [c] gives the amount of drug in body.

Dose = V*[C]

120
Q

What are three (3) factors that can affect apparent volume of distribution

A
  1. Tissue affinity
  2. Protein binding
  3. Transporters
121
Q

Define lag time

A

the delay that occurs between drug administration and the beginning of absorption.

122
Q

What are three factors that oral dose absorption depends on?

A
  1. Physicochemical properties of the drug
  2. Drug product/formulation
  3. Physiology of the site of absorption (small intestine favored)
123
Q

What are three (3) factors contributing to the high rate of absorption in the small intestine?

A
  1. Immense surface area
  2. Blood flow
  3. Permeability
124
Q

What is the First-Pass Effect?

A

A phenomenon where a large amount of drug is eliminated on the first pass through the hepatic portal vein before entering the systemic circulation.

125
Q

What is hepatic biotransformation?

A

Metabolism in the liver.

126
Q

What family of enzymes are especially important in hepatic biotransformation?

A

Cytochrome P450 Enzymes

127
Q

In general, describe the electronic structure of metabolites compared to their parent compound.

A

Metabolites are more polar than their parent compound.

128
Q

Describe phases I and II of Biotransformation

A

Phase I: Chemical Modification of Drug compound (oxidation, reduction, hydrolysis)
Phase 2: chemical addition of functional groups (sulphation, glucoronidation)

129
Q

What are three (3) functions of the Enteral System?

A
  1. Secretion
  2. Digestion
  3. Absorption
130
Q

What is transit time?

A

Time from point A to point B in GI tract. Ingestion to excretion by GI tract is approx. 5 days (total transit time)

131
Q

What is the small intestine transit time?

A

3-4 hours

132
Q

What is the fasted pH of the stomach?

A

about 2-6

133
Q

Describe the pH changes that occur in stomach as food enters

A
  1. Food buffers the stomach, raising pH

2. Parietal cells release HCl, lowering pH

134
Q

Define gastric emptying time

A

How long it takes stomach to empty contents into duodenum

135
Q

Describe the relative gastric emptying times of liquids and solids

A

Liquids empty faster than digested solids when ingested at the same time.

136
Q

What are three (3) functions of the small intestine?

A
  1. Mix food with enzymes to facilitate digestion
  2. Mix intestinal contents with intestinal secretions (enables absorption)
  3. Move unabsorbed materials towards large intestine
137
Q

What is the shortest section of the small intestine?

A

Duodenum - 20-30 cm

138
Q

What is the longest section of the small intestine?

A

Ileum (~3.5 meters)

139
Q

What is the most important section of the small intestine and why? (2 reasons)

A

Duodenum - (1) releases bicarbonate and (2) is major site for passive drug absorption.

140
Q

Define absorption window

A

Anatomic or temporal frame in which a drug is efficiently absorbed in GI tract.

141
Q

What are four (4) factors affecting transit time of a drug in the GI tract

A
  1. Physicochemical properties of the drug
  2. Dosage form
  3. State of the GI tract
  4. Other physiologic factors, such as “fed” or “fasted” state.
142
Q

Define alimentary canal

A

The canal from mouth to anus that food passes through.

143
Q

What are three (3) factors affecting gastric emptying time?

A
  1. Food, esp. Fatty meals
  2. Cold beverages
  3. Anticholinergic drugs
144
Q

Tablets and capsules are delayed from emptying into the duodenum by how much time in the presence of food?

A

About 3 to 6 hours.

145
Q

What three (3) effects can food have on absorption?

A
  1. Enhance absorption
  2. Delay absorption
  3. Reduce absorption
146
Q

In general, what is the relationship between food and bioavailability? (2 components)

A
  1. Bioavailability is greater in a fasted state when a large volume (8 oz) of water is given.
  2. Effects are food will be greatest 10-15 mins after a meal.
147
Q

What are five (5) specific ways food can affect bioavailability?

A
  1. Delay in gastric emptying
  2. Change in the pH of GI tract
  3. Stimulate bile flow
  4. Physical or chemical interaction of the meal with drug substance/formulation
  5. Change in luminal metabolism
148
Q

What are six (6) factors influencing the interaction between food and drug absorption

A
  1. drug substance
  2. drug formulation
  3. local pH
  4. presence of food
  5. transit time through various parts of GI tract
  6. Disease states
149
Q

What affect does food have on drugs with high first-pass metabolism?

A

Food can increase bioavailability, possibly by saturating portal vein enzymes with increased blood flow.

150
Q

What are nine (9) ways disease can affect drug absorption?

A

Changes in:

  1. Intestinal blood flow
  2. GI motility
  3. Stomach emptying time
  4. gastric pH that affects solubility
  5. intestinal pH that affects ionizaton
  6. Permeability of the gut wall
  7. Bile secretion
  8. Secretion of digestive enzymes
  9. Alternation of the normal GI flora
151
Q

What are four (4) disease states that affect drug absorption?

A
  1. Achlorhydria
  2. Short bowel (gut) syndrome
  3. HIV-AIDS
  4. GI Disorders
152
Q

What are two (2) GI disorders?

A
  1. Celiac disease

2. Crohn’s disease

153
Q

How does HIV-AIDS impact drug absorption?

A
  1. Increased gastric transit time
  2. Diarrhea
  3. Achlorhydria
154
Q

What are 5 organs that can be targeted by drug delivery?

A
  1. GI tract (small intestine)
  2. Intravenous delivery
  3. Skin
  4. Brain
  5. Lungs
155
Q

What are four important CQAs of IV products?

A
  1. Sterility
  2. Volume
  3. pH
  4. Tonicity
156
Q

What are three (3) ways to prepare a sterile IV product

A
  1. autoclave
  2. filtration through 0.22 micrometer filter
  3. prepared in aseptic environment
157
Q

How does the volume of IV administration affect pH and tonicity?

A
  1. Small volume injections can be in pH range of 4-10 and hypo or hypertonic.
  2. Large volumes (infusions) must be near pH 6-8 and tonicity varies.
158
Q

What is the brick and mortar model of the skin?

A

A model wherein keratin filled cells lie within an intercellular lipid matrix.

159
Q

What is the rate limiting step for absorption through skin?

A

Drug diffusion through the stratum corneum

160
Q

What type of molecules are more easily absorbed through skin? (2 components)

A
  1. Small molecules (
161
Q

How do the concentrations of drug products delivered through the skin compare to other routes of delivery?

A

Low concentrations required for efficacy. Often very potent drugs on small surface area.

162
Q

What four mechanisms (or lack thereof) form the blood-brain barrier?

A
  1. Tight junctions between capillary and endothelial cells surrounding brain
  2. NO paracellular transport possible
  3. NO pinocytosis
  4. P-gp efflux (MDR1) actively transport molecules out.
163
Q

How do you cross the Blood-Brain barrier (2 ways)

A
  1. highly lipid soluble and low molecular weight

2. specific transporters present

164
Q

Describe the enzyme content of the liver

A

Nearly all of the enzymes for drug metabolism in the liver are found in the lungs

165
Q

What are three (3) advantages of pulmonary delivery versus oral delivery?

A
  1. More rapid onset of action
  2. Less drug required
  3. reduction in likelihood of systemic side effects
166
Q

What happens if a drug particle is delivered to the lung and is too large?

A

Don’t move past upper airways and are rapidly removed

167
Q

What happens if a drug particle is delivered to the lungs and is too small?

A

Will be exhaled out before sedimentation in the alveoli

168
Q

What is the rate-limited step in pulmonary absorption?

A

Transporting across the alveolar membrane

169
Q

What are the three (3) primary physicochemical properties contributing to differential drug absorption

A
  1. Molecular size (generally; small preferred)
  2. Lipophilicity (generally; more lipophilic)
  3. Ionization/charge (unionized more readily cross membrane)
170
Q

What is the Biopharmaceutics Classification System?

A 
A system that classifies drugs into Class I, II, III or IV based on intestinal permeability and solubility. Class I is highly permeable and soluble, class IV is poorly permeable and soluble. 
{II,   I }
{IV, III}
171
Q

What is the pH partition hypothesis?

A

“absorption of a drug substance is based directly on the degree of ionization in the GI lumen and in the blood.”

172
Q

What is the logic behind the pH partition hypothesis?

A

Ion Trapping:

  1. Unionized species travel through membranes more easily.
  2. Many drugs are weak acids – will be protonated in stomach, unprotonated (charged) in blood.
  3. Drugs will cross membrane, become deprotonated, and be unable to recross membrane.

Pharmaceutical Sciences (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions