WorksheetsTransdermal drug delivery systems
Total questions: 54
Worksheet time: 31mins
Transdermal Scop
FIRST transdermal patch approved by the FDA (1979)
A circular film 0.2 mm thick and 2.5 cm2
Designed for continuous release (5 ug/h over 72h) of scopolamine
Used to prevent nausea and vomiting associated with travel
Applies on the skin behind the ear
Alkaloid extracted from Solanaceae
Scopolamine
Nicotrol
Duragesic
Properties of Scopolamine
C17H21NO4
Mw= 303 g/mol
potent opioid analgesic
Oral bioavailability
Scopolamine undergoes second-pass metabolism and has a half-life of ~4.5h
true
false
The application of a formulation to the skin to deliver a drug through the SKIN into the general CIRCULATION for a SYSTEMIC effect.
Reservoir systems
Permeation enhancement
Transdermal transport
Movement of drug through the membrane
Diffusion
Partitioning
Permeation
Permeants
Penetration
The chemicals species moving through or into the tissue
Permeation
Permeants
Diffusion
Partitioning
Penetration
Distributing of molecules between two domains
Permeation
Permeants
Diffusion
Percutaneous absorption
Partitioning
Movement of molecules by random molecular movement, from high concentration to low concentration
Partitioning
Percutaneous absorption
Diffusion
Permeant
Penetration
Entry of molecules into the tissue
Permeation
Penetration
Percutaneous absorption
Permeants
Partitioning
The absorption of drugs through intact skin
Penetration
Permeation
Percutaneous absorption
Partitioning
Permeants
During the transdermal transport, what are the main routes?
Intracellular/ transcellular
Extracellular
Intercellular
Travels through a double layer
Intercellular route
Transcellular route
Shunt routes:
Via the sweat pores
Through the corneocyte and intracellular space
Through the hair follicles with the associated sebaceous glans
The partition is into corneocyte
Intracellular/ transcellular route
Intercellular route
KNOW THIS
yes
no
Factors affecting permeation
physiological factors
physiochemical properties of a permeant
formulation factors
manufacturer brand
Which of the following are part of the physiological factors that affect permeation?
body site
race and age
pathological conditions of the skin
molecular weight (100-500 Da)
skin hydration (hydration favors percutaneous absorption)
Which of the following are part of the physiochemical properties that affects permeation?
molecular weight (100-500 Da)
Partition coefficients
Drug concentration
Effective dose of a drug
Surface area
MW <500 Da is believed to be ideal for TDDS
true
false
Physiochemical properties can affect permeation. In those physiochemical properties, the partition coefficient is included and it is said that Log P values between 1-7 are preferable.
true
false
Physiochemical properties can affect permeation. In those physiochemical properties, the partition coefficient is included and it is said that Non polar drugs tend to cross the cell barrier through a lipid-rich regions (trans cellular route)
true
false
Physiochemical properties can affect permeation. In those physiochemical properties, the partition coefficient is included and it is said that Polar drugs favor transport between cells (intercellular route)
true
false
The effective dose of a drug must be relatively high (~10 mg/day)
true
false
Which of the following are part of the formulation factors that affects permeation?
Drug concentration
pH of the vehicle and surface area
The larger the TDDS, the more drug is absorbed
The effective dose of a drug
Exposure time
The amount of drug absorbed percutaneously increases with a decrease in the concentration of the drug in the TTDS.
true
false
Advantages of TDDS
Bypassing the first-pass metabolism
Provides continuous and controlled drug delivery
Avoiding GI degradation/irritation
Can be self-administered
Bypassing the second-pass metabolism
Advantages of TDDS
Noninvasive and painless ROA, and thus patient firengldy
Therapy can be initiated and terminated as needed
Generally expensive
Generally inexpensive
Transdermal vaccine delivery could improve immune responses by targeting delivery to immunogenic cells in the skin
A dosage form designed to deliver a constant and controlled therapeutic dosage across skin over extended periods of time for systemic therapy
Transdermal patch
Intravenous route
Controlled release products
Types of transdermal patches (multiple-layers systems):
Drug in adhesive (DIA)
Drug in Matrix
Reservoir system
Drug in layers (DIL)
In the types of transdermal patches, what are the matrix systems?
Drug in adhesive (DIA)
Reservoir system
Drug in layers (DIL)
Drug in matrix
Backing layer, drug in adhesive line
Drug in adhesive (DIA)
Matrix type
(Drug in matrix)
Reservoir system
Backing layer, drug matrix adhesive liner
Drug in adhesive (DIA)
matrix-type
(drug in matrix)
Reservoir system
Backing layer, drug reservoir, membrane adhesive liner
drug in adhesive (DIA)
matrix-type
(drug in matrix)
reservoir system
Drug in adhesive (DIA)
Matrix-type
(drug in matrix)
Reservoir system
Drug in adhesive (DIA)
Matrix-type
(Drug in matrix)
Reservoir system
Drug in adhesive (DIA)
Matrix-type
(drug in matrix)
Reservoir system
DIA systems are the most commonly used
true
false
How many formulation steps does the matrix systems have?
4
2
5
3
What is the formulation steps order?
1. Applying a linear
2. The solution/dispersion casting
3. Coating by a backing layer
4. Dissolving or dispersing a drug in an adhesive polymer solution
5. Drying
1,2,3,4,5
4,2,5,3,1
4,2,5,1,3
5,3,2,4,1
The disadvantage of the technology in matrix systems is the low drug loading
true
false
Nicotrol is considered a DIA system
true
false
Nicotrol ans DIA system:
Smoking cessation nicotine (15 mg/6h) patch
The API is sandwiched between backing layer and liner
The polymer matrix controls the drug release rate
Prepared by dissolving the drug and polymers in a common solvent, cast as the matrix and dried
The polymer matrix does not controls the drug release rate
Nicotrol as a DIA System:
Laminated Polyester film
Non-disposable liner
Adhesive, non-woven material, Nicotine
Disposable liner
Formulation factors includes drug concentration that can be of a finite and infinite dosing
true
false
Drug- matrix Types inludes:
Finite dose formulations
Positive dose formulations
Negative dose formulations
Infinite dose formulations
This type of dose formulation is WITHOUT excess of drug
Finite
Positive
Negative
Infinite
This type of dose formulation is WITH excess of drug
Finite
Positive
Negative
Infinite
Maintain saturation at the stratum corneum layer as long as the level of a drug in the device exceeds the solubility limit of the stratum corneum
Finite dose formulation
Positive dose formulations
Negative dose formulations
Infinite dose formulation
A drug reserve is used to assure continued drug saturation at the stratum corneum
Finite dose formulations
Positive dose formulations
Negative dose formulations
Infinite drug formulations
Typical permeation profile for:
Finite dose application
Infinite dose application
Typical permeation profile for:
Finite dose application
Infinite dose application
In which of the following are you going to have a plateau phase?
Finite dose application profile
Infinite application profile
In which of the following are you going to have a steady state slope?
Finite dose application profile
Infinite dose application profile
