E2 L6 - Controlled Drug Delivery 1

Question 1

Temporal drug delivery

Answer 1

Sustained release
Looking to released in hours instead of minutes
Delayed
Extended
Pulsatile release

Question 2

Spatial drug delivery

Answer 2

Systemic
Local
Targeted
Ie. treating cancer - want to address diseased cells, but not kill the healthy cells
More of dose to cancer cells, less to healthy cells

Question 3

Potential advantages of controlled drug delivery

Answer 3

Maintain optimum drug concentrations

Improve efficiency of treatment with less amount of drug

Minimize side effects

Less frequent admin

Increase patient convenience and compliance with dosing regimen

Controlled release device – maintain therapeutic window for a longer time

Question 4

Disadvantages of controlled drug release

Answer 4

Relatively high production costs

Leakage of drug mass (Dose dumping)

Difficult to stop drug release

Biocompatibility of the delivery systems?

Necessity of surgical operation

In a controlled release device, make sure patients do not chew the tablets – dose dumping

Question 5

Temporal control of drug delivery: Needed for

Answer 5

Optimizing drug concentration - time profiles at the site of action
Reducing administration frequency of the drugs
Stimulating multiple dosing via combination of an immediate-release dosage and a pulsatile delivery system

Question 6

Temporal control of drug delivery not needed for:

Answer 6

Drugs with a long half-life
Drugs of which long-term effect is undesirable
Drugs which require immediate effect

Question 7

Drug release control mechanisms

Answer 7

Diffusion-controlled systems

Reservoir Devices

Matrix devices

Dissolution-controlled systems

Erosion-controlled systems

Osmotic systems

Swelling systems

Question 8

Diffusion-controlled systems

Answer 8

Drug diffusion through the polymer network is the rate-limiting step

Question 9

Diffusion controlled systems two types

Answer 9

Reservoir
Matrix

Question 10

Ocusert

Answer 10

Not very effective