Term
|
Definition
| Passage of drug from site of administration and into the blood |
|
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Term
T/F
The mouth is the first site of administration of a drug |
|
Definition
FALSE
The site of administration is where the drug gets absorbed by the body...GI, Intestines Lungs etc. |
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Term
What factors effect drug absorption?
(6) |
|
Definition
Drug solubility/dissolution
Lipophilicity
Molecular weight
Particle Size
Polymorphic Forms
Acid Base Properties |
|
|
Term
| Most drugs are weak/strong, organic/inorganic acids and bases? |
|
Definition
| Weak, organic acids and bases |
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Term
T/F
By knowing the pKa of drugs A and B , one can determine which one will be absorbed faster? |
|
Definition
False
must also consider other factors
Barbital pKa= 7.8
Secobarbitol pKa= 7.9
Thiopental pKa= 7.6
Absorption: Thiopental>Secobarbitol> Barbitol
Due to lipophilicty (see notes) |
|
|
Term
How does MOLECULAR WEIGHT determine absorption?
How does PARTICLE SIZE determine absorption?
|
|
Definition
The larger a molecule the slower its absorption
The finer the part. size the faster its absorption |
|
|
Term
How does acid/base properties det. absorption?
Which form of a molecule gets absorbed? (ion/unionized) |
|
Definition
Ionization depends on the pKa of the drug and the pH of the tissue-->absorption
The unionized form gets absorbed |
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Term
| Even though the unionized form of Aspirin predominates in the stomach, why is it still readily absorbed in the intestines? |
|
Definition
| The large surface area and times spent in the intestines allows for it to be absorbed |
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Term
T/F
Equilibrium means that the amounts on each side of the equation stays the same |
|
Definition
FALSE
It means the ratio stays the same NOT amount |
|
|
Term
How can the following be altered to alter absorption?
A) Drug Concentration
B) Blood Flow
C) transporters |
|
Definition
A) Alter dose...inc. C1 inc. absorption
B) Warmth > inc. blood flow> dec C2 and shifts equilibrium to right
C) presence of active transporters can influx/efflux drug |
|
|
Term
| Types of Parenteral administration |
|
Definition
|
|
Term
| Types of Enteral Administration |
|
Definition
|
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Term
| Advantages and Disadv. of Oral Administration |
|
Definition
Advantages
relatively safe, not painful
self-administration, economical
Disadvantages
patient compliance, variable absorption
destruction of drug
active transporters, first pass effect |
|
|
Term
What is the direction of a drug exposed to Intestinal Efflux pumps?
Does it increase or decrease absorption?
What is its purpose?
|
|
Definition
From blood back into gut lumen
Decrease absorption
Protection from ingesting toxic chemicals |
|
|
Term
| What is the first pass effect? |
|
Definition
| After absorption the drug gets sent to the liver first and is possibly metabolized |
|
|
Term
T/F
Advantage of rectal administration is that it doesnt get "first pass metabolism" |
|
Definition
FALSE
Still subject to metabolism by the liver |
|
|
Term
T/F for IV administration
A) very rapid onsent
B) suitable for lipophilic drugs
C) suitable for large volumes
D) must be perfused slowly
|
|
Definition
A) TRUE
B) FALSE-drug will precipitate
C) TRUE
D) TRUE |
|
|
Term
| What is the challenge with transdermal administration? |
|
Definition
| Skin permeability- very lipophilic and no active transport available must use passive diffusion |
|
|
Term
T/F
Particle size is not a factor when administering a drug via pulmonary |
|
Definition
| FALSE if too large drug wont be inhaled |
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