Drug Delivery Systems

Question 1

What are the 4 main types of drug delivery?

Answer 1

Oral

Injection based

Transdermal

Carrier-based

Question 2

Different drugs

Answer 2

Tablets, 
solutions/suspensions, 
Ointments and creams 
Inhalation
Injections
Suppositories
Pessaries

Question 3

Dosage regime factors?

Answer 3

The Dose of drug to be given

Frequency of administration
Timing of administration

Question 4

Choosing a dosage

Answer 4

Find out recommended dosage (BNF/BNFC)
Impaired renal function? Hepatic function?
Consider age and weight
Consider disease
Consider drug toxicity
Starting dose - increase until desired result is achieved.

Question 5

Oral medication

Answer 5

Via GI tract

Buccal
Sublingual
Oral
Rectal

Question 6

Solutions

Answer 6

Can be expensive

Question 7

Suspensions

Answer 7

Dispersions of coarse particles in liquid phase

Question 8

Are tablets stable?

Answer 8

Yes, highly stable

Question 9

Enteric coated tablets

Answer 9

Coating only breaks up when reaches a more alkaline environment. (Protects drug from stomach acid)

Question 10

Prolonged release formulations

Answer 10

Improve compliance, much less scope to forget

Cannot swap from one to another *

Question 11

Parenteral preparations

Answer 11

Intramuscular injections

Question 12

Pro drugs

Answer 12

…

Question 13

Sublingual administration

Answer 13

Dissolve slowly under younger

Most common - GTN for angina

Question 14

What are very commonly used in France?

Answer 14

Suppositories

Question 15

Suppositories, creams and liquids

Answer 15

Useful in young and old and those who cannot swallow

Question 16

What are pessaries?

Answer 16

Drugs used through vagina route

Question 17

Injection-based

Answer 17

Sub-cut
Sub-dermal
Intramuscular - muscle can start to disintegrate

Question 18

IV administration used when?

Answer 18

Rapid onset of action is required,

Careful control of plasma levels required

Slowly given - to prevent toxic effects

Continuous infusion

Question 19

Transdermal delivery

Answer 19

Adhesive patches

Diffuses by percutaneous absorption - goes into systemic circulation

Question 20

Percutaneous

Answer 20

Creams
Ointments
Skin patches

Question 21

Inhalation

Answer 21

Advantage - drug direct, rapid effect

Disadvantage - patient education necessary

Question 22

What is an inhaler spacer?

Answer 22

Tube to go on end of inhaler - makes it easier for patients who are struggling with inhaler

Question 23

Carrier - based drug delivery system

Answer 23

Micelles - vesicles, carry drug inside
Monoclonal antibodies - linked to cytotoxic agent
Liposomes - lipid layer - allows absorption
Nanoparticles -

Question 24

Genetic transfer system

Answer 24

(GEne transfer)

Question 25

Colour of tablets

Answer 25

Colours/ shapes/ words on can influence the effect!!

Question 26

What are the three main principle mechanisms of renal drug excretion?

Answer 26

Glomerular filtration Active tubular secretion Passive tubular reabsorption

Question 27

What is glomerular filtration

Answer 27

Flow rate of filtered fluid through kidney

Question 28

What is active tubular secretion?

Answer 28

Transfer of materials from peritubular capillaries to renal tubular lumen

Question 29

What is passive tubular reabsorption?

Answer 29

Solutes and water removed from tubular fluid and transported into blood

Question 30

What is first pass metabolism?

Answer 30

The metabolism of the drug before it reaches systemic circulation so effect can be unexpected