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Flashcards in Drug Absorption Deck (65)
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1

What is the pharmaceutical process

Getting the drug into the patient

2

What is the pharmacokinetic process

Getting the drug to the site of action

3

What is the pharmacodynamic process

Producing the correct pharmacological effect

4

What is the therapeutic process

Producing the correct therapeutic effect

5

What factors determine drug pharmacokinetics

Absorption
Distribution
Metabolism
Elimination
(ADME)

6

What do the factors of pharmaknetics enable us to understand

Dosage
Drug administration
Drug handling
Patient variability
Potential for harm

7

What is absorption in relation to pharmakinetics

The process of movement of unchanged drug from the site of administration to the systemic circulation

8

How can drugs be absorbed into the system

Oral
Intravenous
Subcutaneous
Intramuscular
Other GI - Sublingual, rectal
Inhalation
Nasal
Transdermal

9

What enables most drugs to have biological action

Drugs must enter the blood stream and be distributed to a site of action

10

There is always a correlation between plasma concentration of a drug and what

The therapeutic response

11

What is Tmax

Time to peak concentration

12

What is Cmax

The peak concentration

13

What is AUC

Area under the drug concentration-time curve which represents the amount of drug which reaches the systemic circulation

14

If the rate of absorption is rapid what happens to the drug concentration peak

It will be earlier (Tmax)

15

If the drug dose is increases what happens

Time to peak concentration will not be affected (Tmax)
Peak concentration will increase (Cmax)

16

What is a therapeutic range

A drug is active over a range of concentrations

17

What happens below and above the therapeutic range

Below: insufficient or no pharmacological action
Above: toxicity

18

What is a therapeutic index

A measure of the range at which a drug is safe and active

19

What is bioavailability

The amount of drug which reaches circulation and which is available for action

20

How can bioavailability be estimated

Using AUC

21

How much bioavailability does a drug given intravenously have

100%

22

State the factors which can affect bioavailability

Formulation
Ability of drug to pass physiological barriers
Gastrointestinal effects
First pass metabolism

23

How does formulation affect bioavailability

Due to the slow release preparations

24

What physiological barriers are there that can affect bioavailability

It is dependent on:
Particle size
Lipid solubility
pH and ionisation

25

What gastrointestinal effects affect bioavailability

It is dependent on:
Gut motility
Food
Illness

26

What does the degree of ionisation of drugs depend on

Most drugs are weak acids or bases so they depend on the pH of the environment

27

What forms of the drug will be present in solution

Ionised and un-ionised forms

28

What can the ionised form of the drug not cross

Membrane

29

What will the un-ionised form of the drug do

Distribute across the membrane until equilibrium is reached

30

What is ion trapping

An acidic drug being more concentrated in the compartment with high pH